Can now have right angle pin headers on PCBs.

Fixed bugs right angle pin headers with rows not equal to two. Added more tests for pin headers.
Added M2 dome head screws.
2025-09-03 20:32:35 +02:00 · 2020-09-11 00:20:28 +01:00 · 2020-09-10 18:38:24 +01:00 · 2020-09-10 18:27:56 +01:00 · 2020-09-06 12:33:44 +01:00 · 2020-09-06 12:32:42 +01:00
117 changed files with 1708 additions and 463 deletions
--- a/global_defs.scad
+++ b/global_defs.scad
@@ -52,14 +52,7 @@ $fs = extrusion_width / 2;

 function round_to_layer(z) = ceil(z / layer_height) * layer_height;
 // Some additional named colours
-grey20                          = [0.2, 0.2, 0.2];
-grey30                          = [0.3, 0.3, 0.3];
-grey40                          = [0.4, 0.4, 0.4];
-grey50                          = [0.5, 0.5, 0.5];
-grey60                          = [0.6, 0.6, 0.6];
-grey70                          = [0.7, 0.7, 0.7];
-grey80                          = [0.8, 0.8, 0.8];
-grey90                          = [0.9, 0.9, 0.9];
+function grey(n) = [0.01, 0.01, 0.01] * n;                                          //! Generate a shade of grey to pass to color().
 gold                            = [255/255, 215/255, 0/255];
 brass                           = [255/255, 220/255, 100/255];
 silver                          = [0.75, 0.75, 0.75];
--- a/lib.scad
+++ b/lib.scad
@@ -29,6 +29,7 @@ include <vitamins/batteries.scad>
 include <vitamins/blowers.scad>
 include <vitamins/bulldogs.scad>
 include <vitamins/buttons.scad>
+include <vitamins/cameras.scad>
 include <vitamins/components.scad>
 include <vitamins/displays.scad>
 include <vitamins/extrusions.scad>
@@ -42,6 +43,7 @@ include <vitamins/ldrs.scad>
 include <vitamins/leadnuts.scad>
 include <vitamins/led_meter.scad>
 include <vitamins/light_strips.scad>
+include <vitamins/magnets.scad>
 include <vitamins/mains_sockets.scad>
 include <vitamins/modules.scad>
 include <vitamins/panel_meters.scad>
@@ -83,6 +85,7 @@ use <utils/rounded_cylinder.scad>
 use <utils/dogbones.scad>
 use <utils/tube.scad>
 use <utils/quadrant.scad>
+use <utils/gears.scad>
 use <utils/hanging_hole.scad>
 use <utils/fillet.scad>
 use <utils/rounded_polygon.scad>
--- a/libtest.png
+++ b/libtest.png
--- a/libtest.scad
+++ b/libtest.scad
@@ -29,6 +29,7 @@ use <tests/blowers.scad>
 use <tests/bulldogs.scad>
 use <tests/buttons.scad>
 use <tests/cable_strips.scad>
+use <tests/cameras.scad>
 use <tests/circlips.scad>
 use <tests/components.scad>
 use <tests/d_connectors.scad>
@@ -49,6 +50,7 @@ use <tests/LEDs.scad>
 use <tests/light_strips.scad>
 use <tests/linear_bearings.scad>
 use <tests/LED_meters.scad>
+use <tests/magnets.scad>
 use <tests/microswitches.scad>
 use <tests/modules.scad>
 use <tests/nuts.scad>
@@ -72,7 +74,7 @@ use <tests/spades.scad>
 use <tests/springs.scad>
 use <tests/SSRs.scad>
 use <tests/stepper_motors.scad>
-use <tests/swiss_clips.scad>
+use <tests/Swiss_clips.scad>
 use <tests/toggles.scad>
 use <tests/transformers.scad>
 use <tests/tubings.scad>
@@ -270,8 +272,9 @@ translate([x1, leadnuts_y])

 leds_y = 0;
 carriers_y = leds_y + 40;
-spades_y = carriers_y + 40;
-buttons_y = spades_y + 40;
+magnets_y = carriers_y + 40;
+spades_y = magnets_y + 20;
+buttons_y = spades_y + 20;
 jacks_y = buttons_y + 40;
 microswitches_y = jacks_y + 40;
 rockers_y = microswitches_y + 40;
@@ -287,6 +290,9 @@ translate([x2 + 35, leds_y])
 translate([x2 + 8, carriers_y])
    carriers();

+translate([x2, magnets_y])
+    magnets();
+
 translate([x2 + 20, carriers_y])
    led_meters();

@@ -334,6 +340,9 @@ translate([x3 + 70, veroboard_y + 30])
 translate([x3 + 140, veroboard_y + 20])
    pcb_mounts();

+translate([x3 + 170, veroboard_y + 16])
+    cameras();
+
 translate([x3, d_connectors_y])
    d_connectors();

@@ -381,7 +390,7 @@ sk_brackets_y = extrusion_brackets_y + 80;
 kp_pillow_blocks_y = sk_brackets_y + 50;
 scs_bearing_blocks_y = kp_pillow_blocks_y + 60;

-translate([x4 + 150, belts_y + 58]) {
+translate([x4 + 200, belts_y + 58]) {
    belt_test();

    translate([0, 60])
--- a/printed/box.scad
+++ b/printed/box.scad
@@ -31,29 +31,29 @@
 //!
 //! Normally the side sheets are the same type but they can be overridden individually as long as the substitute has the same thickness.
 //
-include <../utils/core/core.scad>
+include <../core.scad>
 use <../vitamins/sheet.scad>
-use <../vitamins/screw.scad>
-use <../vitamins/washer.scad>
 use <../vitamins/insert.scad>
 use <../utils/quadrant.scad>
+use <../utils/round.scad>

 bezel_clearance = 0.2;
 sheet_end_clearance = 1;
 sheet_slot_clearance = 0.2;

-function box_screw(type)     = type[0]; //! Screw type to be used at the corners
-function box_wall(type)      = type[1]; //! Wall thickness of 3D parts
-function box_sheets(type)    = type[2]; //! Sheet type used for the sides
-function box_top_sheet(type) = type[3]; //! Sheet type for the top
-function box_base_sheet(type)= type[4]; //! Sheet type for the bottom
-function box_feet(type)      = type[5]; //! True to enable feet on the bottom bezel
-function box_width(type)     = type[6]; //! Internal width
-function box_depth(type)     = type[7]; //! Internal depth
-function box_height(type)    = type[8]; //! Internal height
+function box_screw(type)       = type[0]; //! Screw type to be used at the corners
+function box_shelf_screw(type) = type[1]; //! Screw type to hold a shelf
+function box_wall(type)        = type[2]; //! Wall thickness of 3D parts
+function box_sheets(type)      = type[3]; //! Sheet type used for the sides
+function box_top_sheet(type)   = type[4]; //! Sheet type for the top
+function box_base_sheet(type)  = type[5]; //! Sheet type for the bottom
+function box_feet(type)        = type[6]; //! True to enable feet on the bottom bezel
+function box_width(type)       = type[7]; //! Internal width
+function box_depth(type)       = type[8]; //! Internal depth
+function box_height(type)      = type[9]; //! Internal height

-function box(screw, wall, sheets, top_sheet, base_sheet, size, feet = false) = //! Construct a property list for a box.
- concat([screw, wall, sheets, top_sheet, base_sheet, feet], size);
+function box(screw, wall, sheets, top_sheet, base_sheet, size, feet = false, shelf_screw = M3_dome_screw) = //! Construct a property list for a box.
+ concat([screw, shelf_screw, wall, sheets, top_sheet, base_sheet, feet], size);

 function box_bezel_clearance(type) = bezel_clearance;

@@ -62,6 +62,7 @@ function box_profile_overlap(type) = 3 + sheet_end_clearance / 2;

 function box_washer(type) = screw_washer(box_screw(type));
 function box_insert(type) = screw_insert(box_screw(type));
+function box_shelf_insert(type) = screw_insert(box_shelf_screw(type));

 function box_hole_inset(type) = washer_radius(box_washer(type)) + 1;
 function box_insert_r(type) = insert_hole_radius(box_insert(type));
@@ -90,23 +91,32 @@ function box_bezel_height(type, bottom) = //! Bezel height for top or bottom

 grill_hole = 5;
 grill_gap = 1.9;
-module grill(width, height, r = 1000, poly = false, h = 0) { //! A staggered array of 5mm holes to make grills in sheets. Can be constrained to be circular. Set ```poly``` ```true``` for printing, ```false``` for milling.
+
+function box_grill_hole_r() = grill_hole / 2;
+
+module grill_hole_positions(width, height, r = 1000) {
    nx = floor(width / (grill_hole + grill_gap));
    xpitch = width / nx;
    ny = floor(height / ((grill_hole + grill_gap) * cos(30)));
    ypitch = height / ny;

+    for(y = [0 : ny - 1], x = [0 : nx - 1 - (y % 2)]) {
+        $x = -width / 2 + (x + 0.5 + (y % 2) / 2) * xpitch;
+        $y = -height / 2 + (y + 0.5) * ypitch;
+        if(sqrt(sqr($x) + sqr($y)) + grill_hole / 2 <= r)
+            translate([$x, $y])
+                children();
+    }
+}
+
+module grill(width, height, r = 1000, poly = false, h = 0) { //! A staggered array of 5mm holes to make grills in sheets. Can be constrained to be circular. Set ```poly``` ```true``` for printing, ```false``` for milling.
    extrude_if(h)
-        for(y = [0 : ny - 1], x = [0 : nx - 1 - (y % 2)]) {
-            x = -width / 2 + (x + 0.5 + (y % 2) / 2) * xpitch;
-            y = -height / 2 + (y + 0.5) * ypitch;
-            if(sqrt(sqr(x) + sqr(y)) + grill_hole / 2 <= r)
-                translate([x, y])
-                    if(poly)
-                        poly_circle(r = grill_hole / 2);
-                    else
-                        circle(d = grill_hole);
-        }
+        if(poly)
+            grill_hole_positions(width, height, r)
+                poly_circle(r = grill_hole / 2);
+        else
+            grill_hole_positions(width, height, r)
+                circle(d = grill_hole);
 }

 module box_corner_profile_2D(type) { //! The 2D shape of the corner profile.
@@ -178,6 +188,15 @@ module box_corner_profile_section(type, section, sections) { //! Generates inter
    }
 }

+module box_corner_profile_sections(type, section, sections) { //! Generate four copies of a corner profile section
+    stl("box_corner_profile");
+    offset = box_boss_r(type) + 1;
+    for(i = [0 : 3])
+        rotate(i * 90)
+            translate([offset, offset])
+                box_corner_profile_section(type, section, sections);
+}
+
 module box_corner_quadrants(type, width, depth)
    for(corner = [0:3]) {
        x = [-1,1,1,-1][corner];
@@ -261,10 +280,11 @@ dowel_length = 20;
 dowel_wall = extrusion_width * 3;
 dowel_h_wall = layer_height * 6;

-
 module box_bezel_section(type, bottom, rows, cols, x, y) { //! Generates interlocking sections of the bezel to allow it to be bigger than the printer
-    w = (box_width(type) + 2 * box_outset(type)) / cols;
-    h = (box_depth(type) + 2 * box_outset(type)) / rows;
+    tw = box_width(type) + 2 * box_outset(type);
+    w = tw / cols;
+    th = box_depth(type) + 2 * box_outset(type);
+    h = th / rows;
    bw = box_outset(type) - bezel_clearance / 2;
    bw2 = box_outset(type) + box_inset(type);

@@ -339,7 +359,7 @@ module box_bezel_section(type, bottom, rows, cols, x, y) { //! Generates interlo
        render() difference() {
            union() {
                clip(xmin = 0, xmax = w, ymin = 0, ymax = h)
-                    translate([box_width(type) / 2 + box_outset(type) - x * w, box_depth(type) / 2 + box_outset(type) - y * h, box_profile_overlap(type)])
+                    translate([tw / 2 - x * w, th / 2 - y * h, box_profile_overlap(type)])
                        box_bezel(type, bottom);

                if(x < cols - 1 && y == 0)
@@ -399,7 +419,6 @@ module box_bezel_section(type, bottom, rows, cols, x, y) { //! Generates interlo
    }
 }

-
 module box_screw_hole_positions(type)
    for(x = [-1, 1], y = [-1, 1])
        translate([x * (box_width(type) / 2 - box_hole_inset(type)), y * (box_depth(type) / 2 - box_hole_inset(type))])
@@ -442,6 +461,96 @@ module box_shelf_blank(type, sheet = false) { //! Generates a 2D template for a
    }
 }

+module box_shelf_screw_positions(type, screw_positions, thickness = 0, wall = undef) { //! Place children at the shelf screw positions
+    w = is_undef(wall) ? box_wall(type) : wall;
+    insert = box_shelf_insert(type);
+    translate_z(-insert_boss_radius(insert, w))
+        for(p = screw_positions)
+            multmatrix(p)
+                translate_z(thickness)
+                    children();
+}
+
+module box_shelf_bracket(type, screw_positions, wall = undef) { //! Generates a shelf bracket, the first optional child is a 2D cutout and the second 3D cutouts
+    stl("shelf_bracket");
+    w = is_undef(wall) ? box_wall(type) : wall;
+    insert = box_shelf_insert(type);
+    lip = 2 * insert_boss_radius(insert, w);
+    width = insert_length(insert) + w;
+
+    module shape()
+        difference() {
+            square([box_width(type), box_depth(type)], center = true);
+
+            offset(bezel_clearance / 2)
+                box_corner_quadrants(type, box_width(type), box_depth(type));
+
+            if($children)
+                hflip()
+                    children();
+        }
+
+    module boss()
+        translate_z(-width + eps)
+            linear_extrude(width - 2 * eps)
+                hull() {
+                    circle4n(r = lip / 2 - eps);
+
+                    translate([-lip / 2, -lip / 2 + eps])
+                        square([lip, eps]);
+                }
+
+    difference() {
+        union() {
+            linear_extrude(w)
+                difference() {
+                    shape()
+                        if($children)
+                            children(0);
+
+                    round(2) offset(-width)
+                        shape()
+                            if($children)
+                                children(0);
+                }
+
+            linear_extrude(lip)
+                difference() {
+                    shape()
+                        if($children)
+                            children(0);
+
+                    offset(-w)
+                        shape()
+                            if($children)
+                                children(0);
+                }
+
+            hflip()
+                box_shelf_screw_positions(type, screw_positions, 0, w)
+                    boss();
+        }
+        if($children > 1)
+            hflip()
+                children(1);
+
+        hflip()
+            box_shelf_screw_positions(type, screw_positions, 0, w)
+                insert_hole(insert, counterbore = 1, horizontal = true);
+    }
+}
+
+module box_shelf_bracket_section(type, rows, cols, x, y) { //! Generates sections of the shelf bracket to allow it to be bigger than the printer
+    tw = box_width(type);
+    w = tw / cols;
+    th = box_depth(type);
+    h = th / rows;
+
+    clip(xmin = 0, xmax = w, ymin = 0, ymax = h)
+        translate([tw / 2 - x * w, th / 2 - y * h])
+            children();
+}
+
 module box_left_blank(type, sheet = false) { //! Generates a 2D template for the left sheet, ```sheet``` can be set to override the type
    dxf("box_left");

--- a/printed/butt_box.scad
+++ b/printed/butt_box.scad
@@ -110,12 +110,9 @@ function fixing_block_positions(type) = let(

 function side_holes(type) = [for(p = fixing_block_positions(type), q = fixing_block_holes(bbox_screw(type))) p * q];

-module drill_holes(type, t)
-    for(list = [corner_holes(type), side_holes(type)], p = list)
-        let(q = t * p)
-            if(abs(transform([0, 0, 0], q).z) < eps)
-                multmatrix(q)
-                    drill(screw_clearance_radius(bbox_screw(type)), 0);
+module bbox_drill_holes(type, t)
+    position_children(concat(corner_holes(type), side_holes(type)), t)
+        drill(screw_clearance_radius(bbox_screw(type)), 0);

 module bbox_base_blank(type) { //! 2D template for the base
    dxf(str(bbox_name(type), "_base"));
@@ -123,7 +120,7 @@ module bbox_base_blank(type) { //! 2D template for the base
    difference() {
        sheet_2D(bbox_base_sheet(type), bbox_width(type), bbox_depth(type), 1);

-        drill_holes(type, translate(bbox_height(type) / 2));
+        bbox_drill_holes(type, translate(bbox_height(type) / 2));
    }
 }

@@ -136,7 +133,7 @@ module bbox_top_blank(type) { //! 2D template for the top
        translate([0, t / 2])
            sheet_2D(bbox_top_sheet(type), bbox_width(type) + 2 * t, bbox_depth(type) + t);

-        drill_holes(type, translate(-bbox_height(type) / 2));
+        bbox_drill_holes(type, translate(-bbox_height(type) / 2));
    }
 }

@@ -154,7 +151,7 @@ module bbox_left_blank(type, sheet = false) { //! 2D template for the left side
        translate([-t / 2, -bb / 2])
            sheet_2D(subst_sheet(type, sheet), bbox_depth(type) + t, bbox_height(type) + bb);

-        drill_holes(type, rotate([0, 90, 90]) * translate([bbox_width(type) / 2, 0]));
+        bbox_drill_holes(type, rotate([0, 90, 90]) * translate([bbox_width(type) / 2, 0]));
    }
 }

@@ -168,7 +165,7 @@ module bbox_right_blank(type, sheet = false) { //! 2D template for the right sid
        translate([t / 2, -bb / 2])
            sheet_2D(subst_sheet(type, sheet), bbox_depth(type) + t, bbox_height(type) + bb);

-        drill_holes(type, rotate([0, 90, 90]) * translate([-bbox_width(type) / 2, 0]));
+        bbox_drill_holes(type, rotate([0, 90, 90]) * translate([-bbox_width(type) / 2, 0]));
    }
 }

@@ -183,7 +180,7 @@ module bbox_front_blank(type, sheet = false, width = 0) { //! 2D template for th
        translate([0, (bt - bb) / 2])
            sheet_2D(subst_sheet(type, sheet), max(bbox_width(type) + 2 * t, width), bbox_height(type) + bb + bt);

-        drill_holes(type, rotate([-90, 0, 0]) * translate([0, bbox_depth(type) / 2]));
+        bbox_drill_holes(type, rotate([-90, 0, 0]) * translate([0, bbox_depth(type) / 2]));
    }
 }

@@ -197,7 +194,7 @@ module bbox_back_blank(type, sheet = false) { //! 2D template for the back
        translate([0, -bb / 2])
            sheet_2D(subst_sheet(type, sheet), bbox_width(type), bbox_height(type) + bb);

-        drill_holes(type, rotate([-90, 0, 0]) * translate([0, -bbox_depth(type) / 2]));
+        bbox_drill_holes(type, rotate([-90, 0, 0]) * translate([0, -bbox_depth(type) / 2]));
    }
 }

--- a/printed/door_hinge.scad
+++ b/printed/door_hinge.scad
@@ -74,7 +74,7 @@ module door_hinge(door_thickness) {                         //! Generates STL fo
                            square([1, thickness + door_thickness]);
                    }
                    translate([dia / 2, thickness + door_thickness / 2])
-                        teardrop(r = screw_clearance_radius(pin_screw), h = 0);
+                        teardrop_plus(r = screw_clearance_radius(pin_screw), h = 0);
                }
        linear_extrude(thickness)
            difference() {
@@ -127,7 +127,7 @@ module door_hinge_stat_stl() { //! Generates the STL for the stationary part
                            square([dia, 1], center = true);
                    }
                    translate([0, dia / 2 + stat_clearance])
-                        teardrop(r = screw_clearance_radius(pin_screw), h = 0);
+                        teardrop_plus(r = screw_clearance_radius(pin_screw), h = 0);
               }
    }
 }
--- a/printed/ssr_shroud.scad
+++ b/printed/ssr_shroud.scad
@@ -135,7 +135,7 @@ module ssr_shroud_fastened_assembly(type, cable_d, thickness, name) //! Assembly

            *translate_z(cable_d / 2)
                rotate([90, 0, 0])
-                    stl_colour(grey20)
+                    stl_colour(grey(20))
                        cylinder(d = cable_d, h = 20, center = true);
        }
 }
--- a/readme.md
+++ b/readme.md
@@ -22,26 +22,26 @@ See [usage](docs/usage.md) for requirements, installation instructions and a usa
 <tr><td> <a href = "#Ball_bearings">Ball_bearings</a> </td><td> <a href = "#KP_pillow_blocks">KP_pillow_blocks</a> </td><td> <a href = "#Ring_terminals">Ring_terminals</a> </td><td> <a href = "#Butt_box">Butt_box</a> </td><td> <a href = "#Bezier">Bezier</a> </td><td> <a href = "#Clip">Clip</a> </td></tr>
 <tr><td> <a href = "#Batteries">Batteries</a> </td><td> <a href = "#LDRs">LDRs</a> </td><td> <a href = "#Rockers">Rockers</a> </td><td> <a href = "#Cable_grommets">Cable_grommets</a> </td><td> <a href = "#Dogbones">Dogbones</a> </td><td> <a href = "#Global">Global</a> </td></tr>
 <tr><td> <a href = "#Belts">Belts</a> </td><td> <a href = "#LED_meters">LED_meters</a> </td><td> <a href = "#Rod">Rod</a> </td><td> <a href = "#Carriers">Carriers</a> </td><td> <a href = "#Fillet">Fillet</a> </td><td> <a href = "#Polyholes">Polyholes</a> </td></tr>
-<tr><td> <a href = "#Blowers">Blowers</a> </td><td> <a href = "#LEDs">LEDs</a> </td><td> <a href = "#SCS_bearing_blocks">SCS_bearing_blocks</a> </td><td> <a href = "#Corner_block">Corner_block</a> </td><td> <a href = "#Hanging_hole">Hanging_hole</a> </td><td> <a href = "#Rounded_rectangle">Rounded_rectangle</a> </td></tr>
-<tr><td> <a href = "#Bulldogs">Bulldogs</a> </td><td> <a href = "#Leadnuts">Leadnuts</a> </td><td> <a href = "#SK_brackets">SK_brackets</a> </td><td> <a href = "#Door_hinge">Door_hinge</a> </td><td> <a href = "#Layout">Layout</a> </td><td> <a href = "#Sphere">Sphere</a> </td></tr>
-<tr><td> <a href = "#Buttons">Buttons</a> </td><td> <a href = "#Light_strips">Light_strips</a> </td><td> <a href = "#SMDs">SMDs</a> </td><td> <a href = "#Door_latch">Door_latch</a> </td><td> <a href = "#Maths">Maths</a> </td><td> <a href = "#Teardrops">Teardrops</a> </td></tr>
-<tr><td> <a href = "#Cable_strips">Cable_strips</a> </td><td> <a href = "#Linear_bearings">Linear_bearings</a> </td><td> <a href = "#SSRs">SSRs</a> </td><td> <a href = "#Fan_guard">Fan_guard</a> </td><td> <a href = "#Offset">Offset</a> </td><td></td></tr>
-<tr><td> <a href = "#Circlips">Circlips</a> </td><td> <a href = "#Mains_sockets">Mains_sockets</a> </td><td> <a href = "#Screws">Screws</a> </td><td> <a href = "#Fixing_block">Fixing_block</a> </td><td> <a href = "#Quadrant">Quadrant</a> </td><td></td></tr>
-<tr><td> <a href = "#Components">Components</a> </td><td> <a href = "#Microswitches">Microswitches</a> </td><td> <a href = "#Sealing_strip">Sealing_strip</a> </td><td> <a href = "#Flat_hinge">Flat_hinge</a> </td><td> <a href = "#Round">Round</a> </td><td></td></tr>
-<tr><td> <a href = "#DIP">DIP</a> </td><td> <a href = "#Microview">Microview</a> </td><td> <a href = "#Sheets">Sheets</a> </td><td> <a href = "#Foot">Foot</a> </td><td> <a href = "#Rounded_cylinder">Rounded_cylinder</a> </td><td></td></tr>
-<tr><td> <a href = "#D_connectors">D_connectors</a> </td><td> <a href = "#Modules">Modules</a> </td><td> <a href = "#Spades">Spades</a> </td><td> <a href = "#Handle">Handle</a> </td><td> <a href = "#Rounded_polygon">Rounded_polygon</a> </td><td></td></tr>
-<tr><td> <a href = "#Displays">Displays</a> </td><td> <a href = "#Nuts">Nuts</a> </td><td> <a href = "#Spools">Spools</a> </td><td> <a href = "#PCB_mount">PCB_mount</a> </td><td> <a href = "#Sector">Sector</a> </td><td></td></tr>
-<tr><td> <a href = "#Extrusion_brackets">Extrusion_brackets</a> </td><td> <a href = "#O_ring">O_ring</a> </td><td> <a href = "#Springs">Springs</a> </td><td> <a href = "#PSU_shroud">PSU_shroud</a> </td><td> <a href = "#Sweep">Sweep</a> </td><td></td></tr>
-<tr><td> <a href = "#Extrusions">Extrusions</a> </td><td> <a href = "#Opengrab">Opengrab</a> </td><td> <a href = "#Stepper_motors">Stepper_motors</a> </td><td> <a href = "#Printed_box">Printed_box</a> </td><td> <a href = "#Thread">Thread</a> </td><td></td></tr>
-<tr><td> <a href = "#Fans">Fans</a> </td><td> <a href = "#PCB">PCB</a> </td><td> <a href = "#Swiss_clips">Swiss_clips</a> </td><td> <a href = "#Ribbon_clamp">Ribbon_clamp</a> </td><td> <a href = "#Tube">Tube</a> </td><td></td></tr>
-<tr><td> <a href = "#Fuseholder">Fuseholder</a> </td><td> <a href = "#PCBs">PCBs</a> </td><td> <a href = "#Toggles">Toggles</a> </td><td> <a href = "#SSR_shroud">SSR_shroud</a> </td><td></td><td></td></tr>
-<tr><td> <a href = "#Geared_steppers">Geared_steppers</a> </td><td> <a href = "#PSUs">PSUs</a> </td><td> <a href = "#Transformers">Transformers</a> </td><td> <a href = "#Screw_knob">Screw_knob</a> </td><td></td><td></td></tr>
-<tr><td> <a href = "#Green_terminals">Green_terminals</a> </td><td> <a href = "#Panel_meters">Panel_meters</a> </td><td> <a href = "#Tubings">Tubings</a> </td><td> <a href = "#Socket_box">Socket_box</a> </td><td></td><td></td></tr>
-<tr><td> <a href = "#Hot_ends">Hot_ends</a> </td><td> <a href = "#Pillars">Pillars</a> </td><td> <a href = "#Variacs">Variacs</a> </td><td> <a href = "#Strap_handle">Strap_handle</a> </td><td></td><td></td></tr>
-<tr><td> <a href = "#Hygrometer">Hygrometer</a> </td><td> <a href = "#Pin_headers">Pin_headers</a> </td><td> <a href = "#Veroboard">Veroboard</a> </td><td></td><td></td><td></td></tr>
-<tr><td> <a href = "#IECs">IECs</a> </td><td> <a href = "#Pulleys">Pulleys</a> </td><td> <a href = "#Washers">Washers</a> </td><td></td><td></td><td></td></tr>
-<tr><td> <a href = "#Inserts">Inserts</a> </td><td></td><td> <a href = "#Wire">Wire</a> </td><td></td><td></td><td></td></tr>
-<tr><td></td><td></td><td> <a href = "#Zipties">Zipties</a> </td><td></td><td></td><td></td></tr>
+<tr><td> <a href = "#Blowers">Blowers</a> </td><td> <a href = "#LEDs">LEDs</a> </td><td> <a href = "#SCS_bearing_blocks">SCS_bearing_blocks</a> </td><td> <a href = "#Corner_block">Corner_block</a> </td><td> <a href = "#Gears">Gears</a> </td><td> <a href = "#Rounded_rectangle">Rounded_rectangle</a> </td></tr>
+<tr><td> <a href = "#Bulldogs">Bulldogs</a> </td><td> <a href = "#Leadnuts">Leadnuts</a> </td><td> <a href = "#SK_brackets">SK_brackets</a> </td><td> <a href = "#Door_hinge">Door_hinge</a> </td><td> <a href = "#Hanging_hole">Hanging_hole</a> </td><td> <a href = "#Sphere">Sphere</a> </td></tr>
+<tr><td> <a href = "#Buttons">Buttons</a> </td><td> <a href = "#Light_strips">Light_strips</a> </td><td> <a href = "#SMDs">SMDs</a> </td><td> <a href = "#Door_latch">Door_latch</a> </td><td> <a href = "#Horiholes">Horiholes</a> </td><td> <a href = "#Teardrops">Teardrops</a> </td></tr>
+<tr><td> <a href = "#Cable_strips">Cable_strips</a> </td><td> <a href = "#Linear_bearings">Linear_bearings</a> </td><td> <a href = "#SSRs">SSRs</a> </td><td> <a href = "#Fan_guard">Fan_guard</a> </td><td> <a href = "#Layout">Layout</a> </td><td></td></tr>
+<tr><td> <a href = "#Cameras">Cameras</a> </td><td> <a href = "#Magnets">Magnets</a> </td><td> <a href = "#Screws">Screws</a> </td><td> <a href = "#Fixing_block">Fixing_block</a> </td><td> <a href = "#Maths">Maths</a> </td><td></td></tr>
+<tr><td> <a href = "#Circlips">Circlips</a> </td><td> <a href = "#Mains_sockets">Mains_sockets</a> </td><td> <a href = "#Sealing_strip">Sealing_strip</a> </td><td> <a href = "#Flat_hinge">Flat_hinge</a> </td><td> <a href = "#Offset">Offset</a> </td><td></td></tr>
+<tr><td> <a href = "#Components">Components</a> </td><td> <a href = "#Microswitches">Microswitches</a> </td><td> <a href = "#Sheets">Sheets</a> </td><td> <a href = "#Foot">Foot</a> </td><td> <a href = "#Quadrant">Quadrant</a> </td><td></td></tr>
+<tr><td> <a href = "#DIP">DIP</a> </td><td> <a href = "#Microview">Microview</a> </td><td> <a href = "#Spades">Spades</a> </td><td> <a href = "#Handle">Handle</a> </td><td> <a href = "#Round">Round</a> </td><td></td></tr>
+<tr><td> <a href = "#D_connectors">D_connectors</a> </td><td> <a href = "#Modules">Modules</a> </td><td> <a href = "#Spools">Spools</a> </td><td> <a href = "#PCB_mount">PCB_mount</a> </td><td> <a href = "#Rounded_cylinder">Rounded_cylinder</a> </td><td></td></tr>
+<tr><td> <a href = "#Displays">Displays</a> </td><td> <a href = "#Nuts">Nuts</a> </td><td> <a href = "#Springs">Springs</a> </td><td> <a href = "#PSU_shroud">PSU_shroud</a> </td><td> <a href = "#Rounded_polygon">Rounded_polygon</a> </td><td></td></tr>
+<tr><td> <a href = "#Extrusion_brackets">Extrusion_brackets</a> </td><td> <a href = "#O_ring">O_ring</a> </td><td> <a href = "#Stepper_motors">Stepper_motors</a> </td><td> <a href = "#Printed_box">Printed_box</a> </td><td> <a href = "#Sector">Sector</a> </td><td></td></tr>
+<tr><td> <a href = "#Extrusions">Extrusions</a> </td><td> <a href = "#Opengrab">Opengrab</a> </td><td> <a href = "#Swiss_clips">Swiss_clips</a> </td><td> <a href = "#Ribbon_clamp">Ribbon_clamp</a> </td><td> <a href = "#Sweep">Sweep</a> </td><td></td></tr>
+<tr><td> <a href = "#Fans">Fans</a> </td><td> <a href = "#PCB">PCB</a> </td><td> <a href = "#Toggles">Toggles</a> </td><td> <a href = "#SSR_shroud">SSR_shroud</a> </td><td> <a href = "#Thread">Thread</a> </td><td></td></tr>
+<tr><td> <a href = "#Fuseholder">Fuseholder</a> </td><td> <a href = "#PCBs">PCBs</a> </td><td> <a href = "#Transformers">Transformers</a> </td><td> <a href = "#Screw_knob">Screw_knob</a> </td><td> <a href = "#Tube">Tube</a> </td><td></td></tr>
+<tr><td> <a href = "#Geared_steppers">Geared_steppers</a> </td><td> <a href = "#PSUs">PSUs</a> </td><td> <a href = "#Tubings">Tubings</a> </td><td> <a href = "#Socket_box">Socket_box</a> </td><td></td><td></td></tr>
+<tr><td> <a href = "#Green_terminals">Green_terminals</a> </td><td> <a href = "#Panel_meters">Panel_meters</a> </td><td> <a href = "#Variacs">Variacs</a> </td><td> <a href = "#Strap_handle">Strap_handle</a> </td><td></td><td></td></tr>
+<tr><td> <a href = "#Hot_ends">Hot_ends</a> </td><td> <a href = "#Pillars">Pillars</a> </td><td> <a href = "#Veroboard">Veroboard</a> </td><td></td><td></td><td></td></tr>
+<tr><td> <a href = "#Hygrometer">Hygrometer</a> </td><td> <a href = "#Pin_headers">Pin_headers</a> </td><td> <a href = "#Washers">Washers</a> </td><td></td><td></td><td></td></tr>
+<tr><td> <a href = "#IECs">IECs</a> </td><td> <a href = "#Pulleys">Pulleys</a> </td><td> <a href = "#Wire">Wire</a> </td><td></td><td></td><td></td></tr>
+<tr><td> <a href = "#Inserts">Inserts</a> </td><td></td><td> <a href = "#Zipties">Zipties</a> </td><td></td><td></td><td></td></tr>
 </table>

 ---
@@ -85,6 +85,7 @@ Axial components for PCBs.
 |   1 | ```ax_res(res1_4, 47000)``` |  Resistor 47000 Ohms 5% 0.25W |
 |   1 | ```ax_res(res1_2, 8200)``` |  Resistor 8200 Ohms 5% 0.5W |
 |   1 | ```ax_res(res1_2, 8250, tol = 1)``` |  Resistor 8250 Ohms 1% 0.5W |
+|   1 | ```wire_link(0.8, 10.16)``` |  Wire link 0.8mm x 0.4" |


 <a href="#top">Top</a>
@@ -133,7 +134,8 @@ Also single bearing balls are modelled as just a silver sphere and a BOM entry.
 |   1 | ```ball_bearing(BB6201)``` |  Ball bearing 6201-2RS 12mm x 32mm x 10mm |
 |   1 | ```ball_bearing(BB624)``` |  Ball bearing 624-2RS 4mm x 13mm x 5mm |
 |   1 | ```ball_bearing(BB6808)``` |  Ball bearing 6808-2RS 40mm x 52mm x 7mm |
-|   5 | ``` bearing_ball(3)``` |  Steel ball 3mm |
+|   1 | ```ball_bearing(BBSMR95)``` |  Ball bearing SMR95ZZ 5mm x 9mm x 2.5mm |
+|   6 | ``` bearing_ball(3)``` |  Steel ball 3mm |


 <a href="#top">Top</a>
@@ -208,6 +210,7 @@ Only models 2D paths, so not core XY!
 To make the back of the belt run against a smooth pulley on the outside of the loop specify a negative pitch radius.

 By default the path is a closed loop but a gap length and position can be specified to make open loops.
+To draw the gap its XY position is specified by ```gap_pos```. ```gap_pos.z``` can be used to specify a rotation if the gap is not at the bottom of the loop.

 Individual teeth are not drawn, instead they are represented by a lighter colour.

@@ -222,6 +225,7 @@ Individual teeth are not drawn, instead they are represented by a lighter colour
 | Function | Description |
 |:--- |:--- |
 | ```belt_pitch(type)``` | Pitch in mm |
+| ```belt_pitch_height(type)``` | Offset of the pitch radius from the tips of the teeth |
 | ```belt_thickness(type)``` | Total thickness including teeth |
 | ```belt_tooth_height(type)``` | Tooth height |
 | ```belt_width(type)``` | Width in mm |
@@ -230,12 +234,12 @@ Individual teeth are not drawn, instead they are represented by a lighter colour
 | Function | Description |
 |:--- |:--- |
 | ```belt_length(points, gap = 0)``` | Compute belt length given path and optional gap |
-| ```belt_pitch_height(type)``` | Offset of the pitch radius from the tips of the teeth |
+| ```belt_pitch_to_back(type)``` | Offset of the back from the pitch radius |

 ### Modules
 | Module | Description |
 |:--- |:--- |
-| ```belt(type, points, gap = 0, gap_pt = undef, belt_colour = grey20, tooth_colour = grey50)``` | Draw a belt path given a set of points and pitch radii where the pulleys are. Closed loop unless a gap is specified |
+| ```belt(type, points, gap = 0, gap_pos = undef, belt_colour = grey(20)``` | Draw a belt path given a set of points and pitch radii where the pulleys are. Closed loop unless a gap is specified |

 ![belts](tests/png/belts.png)

@@ -243,7 +247,7 @@ Individual teeth are not drawn, instead they are represented by a lighter colour
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
 |   1 | ```belt(GT2x6, [ ... ])``` |  Belt GT2 x 6mm x 128mm |
-|   1 | ```belt(GT2x6, [ ... ], 80, [0, 0.81])``` |  Belt GT2 x 6mm x 694mm |
+|   1 | ```belt(GT2x6, [ ... ], 80, [0, 0])``` |  Belt GT2 x 6mm x 696mm |
 |   1 | ```belt(T2p5x6, [ ... ])``` |  Belt T2.5 x 6mm x 130mm |
 |   1 | ```belt(T5x10, [ ... ])``` |  Belt T5 x 10mm x 130mm |
 |   1 | ```belt(T5x6, [ ... ])``` |  Belt T5 x 6mm x 130mm |
@@ -430,6 +434,45 @@ When the sides are constrained then a circular model is more accurate.
 |   3 | ```cable_strip(20, 25, 100, 30)``` |  Polypropylene strip 189mm x 24mm x 0.8mm |


+<a href="#top">Top</a>
+
+---
+<a name="Cameras"></a>
+## Cameras
+PCB cameras.
+
+
+[vitamins/cameras.scad](vitamins/cameras.scad) Object definitions.
+
+[vitamins/camera.scad](vitamins/camera.scad) Implementation.
+
+[tests/cameras.scad](tests/cameras.scad) Code for this example.
+
+### Properties
+| Function | Description |
+|:--- |:--- |
+| ```camera_connector_pos(type)``` | The flex connector block for the camera itself's position |
+| ```camera_connector_size(type)``` | The flex connector block for the camera itself's size |
+| ```camera_lens(type)``` | Stack of lens parts, can be round, rectanular or rounded rectangular, with optional tapered aperture |
+| ```camera_lens_offset(type)``` | Offset of the lens center from the PCB centre |
+| ```camera_pcb(type)``` | The PCB part of the camera |
+
+### Modules
+| Module | Description |
+|:--- |:--- |
+| ```camera(type)``` | Draw specified PCB camera |
+| ```camera_lens(type, offset = 0)``` | Draw the lens stack, with optional offset for making a clearance hole |
+
+![cameras](tests/png/cameras.png)
+
+### Vitamins
+| Qty | Module call | BOM entry |
+| ---:|:--- |:---|
+|   1 | ```camera(rpi_camera_v1)``` |  Raspberry Pi camera V1 |
+|   1 | ```camera(rpi_camera_v2)``` |  Raspberry Pi camera V2 |
+|   1 | ```camera(rpi_camera)``` |  Raspberry Pi focusable camera |
+
+
 <a href="#top">Top</a>

 ---
@@ -860,7 +903,7 @@ Can draw three styles: solid, open frame and open frame with screw bosses.
 | ---:|:--- |:---|
 |   1 | ```fan(fan120x25)``` |  Fan 120mm x 25mm |
 |   1 | ```fan(fan17x8)``` |  Fan 17mm x 8mm |
-|   1 | ```fan(fan25x10)``` |  Fan 25mm x 10mm |
+|   1 | ```fan(fan25.4x10)``` |  Fan 25.4mm x 10mm |
 |   1 | ```fan(fan30x10)``` |  Fan 30mm x 10mm |
 |   1 | ```fan(fan40x11)``` |  Fan 40mm x 11mm |
 |   1 | ```fan(fan50x15)``` |  Fan 50mm x 15mm |
@@ -1210,6 +1253,7 @@ Heatfit threaded inserts. Can be pushed into thermoplastics using a soldering ir
 | Function | Description |
 |:--- |:--- |
 | ```insert_boss_radius(type, wall)``` | Compute the outer radius of an insert boss |
+| ```insert_nose_length(type, d)``` | The length before the second ring. |

 ### Modules
 | Module | Description |
@@ -1224,7 +1268,7 @@ Heatfit threaded inserts. Can be pushed into thermoplastics using a soldering ir
 ### Vitamins
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
-|   1 | ```insert(F1BM)``` |  Heatfit insert M2 |
+|   1 | ```insert(F1BM2)``` |  Heatfit insert M2 |
 |   1 | ```insert(F1BM2p5)``` |  Heatfit insert M2.5 |
 |   1 | ```insert(F1BM3)``` |  Heatfit insert M3 |
 |   1 | ```insert(F1BM4)``` |  Heatfit insert M4 |
@@ -1554,9 +1598,10 @@ The `light_strip_clip()` module makes a clip to go around the light that can be
 | Function | Description |
 |:--- |:--- |
 | ```light_strip_clip_depth(light)``` | Depth of the clip |
-| ```light_strip_clip_length(light)``` | Outside length |
+| ```light_strip_clip_length(light)``` | Outside length of clip |
 | ```light_strip_clip_slot(light)``` | Clip slot size |
-| ```light_strip_clip_width(light)``` | Outside width |
+| ```light_strip_clip_wall()``` | Clip wall thickness |
+| ```light_strip_clip_width(light)``` | Outside width of clip |
 | ```light_strip_cut_length(type, segs)``` | Calculate cut length given segments |
 | ```light_strip_segments(type, max_length)``` | Calculate the maximum number of segments that fit in max_length |

@@ -1632,6 +1677,36 @@ LMnUU linear bearings.
 |   1 | ```linear_bearing(LM8UU)``` |  Linear bearing LM8UU |


+<a href="#top">Top</a>
+
+---
+<a name="Magnets"></a>
+## Magnets
+Cylindrical and ring magnets.
+
+
+[vitamins/magnets.scad](vitamins/magnets.scad) Object definitions.
+
+[vitamins/magnet.scad](vitamins/magnet.scad) Implementation.
+
+[tests/magnets.scad](tests/magnets.scad) Code for this example.
+
+### Properties
+| Function | Description |
+|:--- |:--- |
+| ```magnet_h(type)``` | Height |
+| ```magnet_id(type)``` | Inside diameter if a ring |
+| ```magnet_od(type)``` | Outer diameter |
+| ```magnet_r(type)``` | Corner radius |
+
+### Modules
+| Module | Description |
+|:--- |:--- |
+| ```magnet(type)``` | Draw specified magnet |
+
+![magnets](tests/png/magnets.png)
+
+
 <a href="#top">Top</a>

 ---
@@ -1943,6 +2018,7 @@ A permanent magnet that can be magnatized and de-magnatized electronically.
 |:--- |:--- |
 | ```opengrab()``` | Draw OpenGrab module |
 | ```opengrab_hole_positions()``` | Position children at the screw positions |
+| ```opengrab_side_hole_positions()``` | Position children at the two 4mm hole |
 | ```opengrab_target()``` | Draw OpenGrab target |

 ![opengrab](tests/png/opengrab.png)
@@ -1950,8 +2026,8 @@ A permanent magnet that can be magnatized and de-magnatized electronically.
 ### Vitamins
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
-|   1 | ```opengrab_target()``` |  OpenGrab  silicon steel target plate |
 |   1 | ```opengrab()``` |  OpenGrab V3 electro permanent magnet |
+|   1 | ```opengrab_target()``` |  OpenGrab silicon steel target plate |


 <a href="#top">Top</a>
@@ -2033,6 +2109,10 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 ### Properties
 | Function | Description |
 |:--- |:--- |
+| ```ff_back(type)``` | Flat flex back section size |
+| ```ff_latch(type)``` | Flat flex latch size |
+| ```ff_mid(type)``` | Flat flex middle section size |
+| ```ff_slot(type)``` | Flat flex slot size |
 | ```hdmi_depth(type)``` | Front to back depth |
 | ```hdmi_height(type)``` | Outside height above the PCB |
 | ```hdmi_height1(type)``` | Inside height at the sides |
@@ -2062,6 +2142,7 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 | ```pcb_coord(type, p)``` | Convert offsets from the edge to coordinates relative to the centre |
 | ```pcb_grid_pos(type, x, y, z = 0)``` | Returns a pcb grid position |
 | ```pcb_screw(type, cap = hs_cap)``` | Mounting screw type |
+| ```pcb_size(type)``` | Length, width and thickness in a vector |

 ### Modules
 | Module | Description |
@@ -2070,7 +2151,7 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 | ```block(size, colour, makes_cutout, cutouts)``` | Draw a coloured cube to represent a random PCB component |
 | ```buzzer(height, diameter, colour)``` | Draw PCB buzzer with specified height, diameter and colour |
 | ```chip(length, width, thickness, colour, cutout = false)``` | Draw a coloured cube to represent a chip, or other rectangular component |
-| ```flat_flex(cutout = false)``` | Draw flat flexistrip connector as used on RPI0 |
+| ```flat_flex(type, cutout = false)``` | Draw flat flexistrip connector as used on RPI0 |
 | ```flex(cutout = false)``` | Draw flexistrip connector |
 | ```hdmi(type, cutout = false)``` | Draw HDMI socket |
 | ```jack(cutout = false)``` | Draw 3.5mm jack |
@@ -2094,6 +2175,7 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 | ```usb_Ax1(cutout = false)``` | Draw USB type A single socket |
 | ```usb_Ax2(cutout = false)``` | Draw USB type A dual socket |
 | ```usb_B(cutout = false)``` | Draw USB B connector |
+| ```usb_C(cutout = false)``` | Draw USB C connector |
 | ```usb_uA(cutout = false)``` | Draw USB micro A connector |

 ![pcb](tests/png/pcb.png)
@@ -2125,7 +2207,11 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 |   1 | ```ax_res(res1_4, 10000)``` |  Resistor 10000 Ohms 5% 0.25W |
 |   1 | ```ax_res(res1_2, 100000)``` |  Resistor 100000 Ohms 5% 0.5W |
 |   1 | ```ax_res(res1_8, 1e+6, tol = 1)``` |  Resistor 1e+6 Ohms 1% 0.125W |
+|   1 | ```smd_led(LED0603, orange)``` |  SMD LED 0603 orange |
 |   1 | ```smd_led(LED0805, red)``` |  SMD LED 0805 red |
+|   1 | ```smd_resistor(RES0603, 1K)``` |  SMD resistor 0603 1K 0.1W |
+|   1 | ```smd_resistor(RES0805, 1K)``` |  SMD resistor 0805 1K 0.125W |
+|   1 | ```smd_resistor(RES1206, 1K)``` |  SMD resistor 1206 1K 0.25W |
 |   1 | ```square_button(button_6mm)``` |  Square button 6mm |
 |   1 | ```pcb(TMC2130)``` |  TMC2130 |
 |   1 | ```green_terminal(gt_5p08, 2)``` |  Terminal block 2 way 0.2" |
@@ -2138,6 +2224,8 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 |   2 | ```green_terminal(gt_3p5, 4)``` |  Terminal block 4 way 3.5mm |
 |   1 | ```terminal_35(4)``` |  Terminal block 4 way 3.5mm |
 |   1 | ```pcb(TestPCB)``` |  Test PCB |
+|   1 | ```wire_link(0.8, 5.08, h = 10.16)``` |  Wire link 0.8mm x 0.2" |
+|   1 | ```wire_link(0.8, 10.16)``` |  Wire link 0.8mm x 0.4" |


 <a href="#top">Top</a>
@@ -2157,6 +2245,10 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 ### Properties
 | Function | Description |
 |:--- |:--- |
+| ```ff_back(type)``` | Flat flex back section size |
+| ```ff_latch(type)``` | Flat flex latch size |
+| ```ff_mid(type)``` | Flat flex middle section size |
+| ```ff_slot(type)``` | Flat flex slot size |
 | ```hdmi_depth(type)``` | Front to back depth |
 | ```hdmi_height(type)``` | Outside height above the PCB |
 | ```hdmi_height1(type)``` | Inside height at the sides |
@@ -2186,6 +2278,7 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 | ```pcb_coord(type, p)``` | Convert offsets from the edge to coordinates relative to the centre |
 | ```pcb_grid_pos(type, x, y, z = 0)``` | Returns a pcb grid position |
 | ```pcb_screw(type, cap = hs_cap)``` | Mounting screw type |
+| ```pcb_size(type)``` | Length, width and thickness in a vector |

 ### Modules
 | Module | Description |
@@ -2194,7 +2287,7 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 | ```block(size, colour, makes_cutout, cutouts)``` | Draw a coloured cube to represent a random PCB component |
 | ```buzzer(height, diameter, colour)``` | Draw PCB buzzer with specified height, diameter and colour |
 | ```chip(length, width, thickness, colour, cutout = false)``` | Draw a coloured cube to represent a chip, or other rectangular component |
-| ```flat_flex(cutout = false)``` | Draw flat flexistrip connector as used on RPI0 |
+| ```flat_flex(type, cutout = false)``` | Draw flat flexistrip connector as used on RPI0 |
 | ```flex(cutout = false)``` | Draw flexistrip connector |
 | ```hdmi(type, cutout = false)``` | Draw HDMI socket |
 | ```jack(cutout = false)``` | Draw 3.5mm jack |
@@ -2218,6 +2311,7 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 | ```usb_Ax1(cutout = false)``` | Draw USB type A single socket |
 | ```usb_Ax2(cutout = false)``` | Draw USB type A dual socket |
 | ```usb_B(cutout = false)``` | Draw USB B connector |
+| ```usb_C(cutout = false)``` | Draw USB C connector |
 | ```usb_uA(cutout = false)``` | Draw USB micro A connector |

 ![pcbs](tests/png/pcbs.png)
@@ -2237,11 +2331,11 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 |   1 | ```pcb(Keyes5p1)``` |  Keyes5.1 Arduino Uno expansion board |
 |   1 | ```pcb(MT3608)``` |  MT3608 boost converter module |
 |   1 | ```pcb(Melzi)``` |  Melzi electronics |
-|   4 |  |  Micro SD card |
+|   5 |  |  Micro SD card |
 |   1 | ```molex_254(2)``` |  Molex KK header 2 way |
 |   1 | ```molex_254(3)``` |  Molex KK header 3 way |
 |  16 | ```nut(M2_nut, nyloc = true)``` |  Nut M2 x 1.6mm nyloc |
-|  30 | ```nut(M2p5_nut, nyloc = true)``` |  Nut M2.5 x 2.2mm nyloc |
+|  34 | ```nut(M2p5_nut, nyloc = true)``` |  Nut M2.5 x 2.2mm nyloc |
 |  16 | ```nut(M3_nut, nyloc = true)``` |  Nut M3 x 2.4mm nyloc |
 |  12 | ```nut(M4_nut, nyloc = true)``` |  Nut M4 x 3.2mm nyloc |
 |   1 | ```pcb(PI_IO)``` |  PI_IO V2 |
@@ -2254,27 +2348,27 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 |   1 | ```pin_socket(2p54header, 13, 2, right_angle = true)``` |  Pin socket 13 x 2 right_angle |
 |   1 | ```pcb(RAMPSEndstop)``` |  RAMPS Endstop Switch |
 |   1 | ```pcb(RPI3)``` |  Raspberry Pi 3 |
+|   1 | ```pcb(RPI4)``` |  Raspberry Pi 4 |
 |   1 | ```pcb(RPI0)``` |  Raspberry Pi Zero |
 |  12 | ```screw(M2_cap_screw, 16)``` |  Screw M2 cap x 16mm |
 |   4 | ```screw(M2_cap_screw, 20)``` |  Screw M2 cap x 20mm |
 |   2 | ```screw(M2p5_cap_screw, 16)``` |  Screw M2.5 cap x 16mm |
 |   4 | ```screw(M2p5_cap_screw, 20)``` |  Screw M2.5 cap x 20mm |
 |   4 | ```screw(M2p5_cap_screw, 25)``` |  Screw M2.5 cap x 25mm |
-|   4 | ```screw(M2p5_cap_screw, 30)``` |  Screw M2.5 cap x 30mm |
+|   8 | ```screw(M2p5_cap_screw, 30)``` |  Screw M2.5 cap x 30mm |
 |   4 | ```screw(M2p5_pan_screw, 20)``` |  Screw M2.5 pan x 20mm |
 |  12 | ```screw(M2p5_pan_screw, 25)``` |  Screw M2.5 pan x 25mm |
 |   4 | ```screw(M3_cap_screw, 16)``` |  Screw M3 cap x 16mm |
 |   8 | ```screw(M3_cap_screw, 30)``` |  Screw M3 cap x 30mm |
 |   4 | ```screw(M3_cap_screw, 35)``` |  Screw M3 cap x 35mm |
-|   4 | ```screw(M4_cap_screw, 30)``` |  Screw M4 cap x 30mm |
-|   8 | ```screw(M4_cap_screw, 35)``` |  Screw M4 cap x 35mm |
+|  12 | ```screw(M4_cap_screw, 35)``` |  Screw M4 cap x 35mm |
 |   1 | ```pcb(TP4056)``` |  TP4056 Li-lon Battery charger module |
 |   3 | ```terminal_35(2)``` |  Terminal block 2 way 3.5mm |
 |   2 | ```green_terminal(gt_2p54, 4)``` |  Terminal block 4 way 0.1" |
 |   1 |  |  USB A to Mini B lead |
 |   1 | ```pcb(WD2002SJ)``` |  WD2002SJ Buck Boost DC-DC converter |
 |  16 | ```washer(M2_washer)``` |  Washer  M2 x 5mm x 0.3mm |
-|  30 | ```washer(M2p5_washer)``` |  Washer  M2.5 x 5.9mm x 0.5mm |
+|  34 | ```washer(M2p5_washer)``` |  Washer  M2.5 x 5.9mm x 0.5mm |
 |  16 | ```washer(M3_washer)``` |  Washer  M3 x 7mm x 0.5mm |
 |  12 | ```washer(M4_washer)``` |  Washer  M4 x 9mm x 0.8mm |
 |   1 | ```pcb(ZC_A0591)``` |  ZC-A0591 ULN2003 driver PCB |
@@ -2293,14 +2387,15 @@ PCBs and perfboard with optional components. The shape can be a rectangle with o
 |   4 | pcb_spacer25140_2.stl |
 |   4 | pcb_spacer25150_2.stl |
 |   4 | pcb_spacer25180.stl |
+|   4 | pcb_spacer25190.stl |
 |   2 | pcb_spacer2570.stl |
 |   4 | pcb_spacer30160.stl |
 |   4 | pcb_spacer30170.stl |
-|   4 | pcb_spacer30220.stl |
+|   4 | pcb_spacer30230.stl |
 |   4 | pcb_spacer3050.stl |
-|   4 | pcb_spacer40190.stl |
 |   4 | pcb_spacer40200.stl |
 |   4 | pcb_spacer40210.stl |
+|   4 | pcb_spacer40220.stl |


 <a href="#top">Top</a>
@@ -2381,7 +2476,7 @@ Pin headers and sockets, etc.
 |:--- |:--- |
 | ```box_header(type, cols = 1, rows = 1, smt = false, cutout = false)``` | Draw box header |
 | ```idc_transition(type, cols = 5, skip = [], cutout = false)``` | Draw IDC transition header |
-| ```jst_xh_header(type, pin_count, right_angle=false, colour, pin_colour)``` | Draw JST XH connector |
+| ```jst_xh_header(type, pin_count, right_angle=false, colour = false, pin_colour = false)``` | Draw JST XH connector |
 | ```pin(type, length = undef)``` | Draw a header pin |
 | ```pin_header(type, cols = 1, rows = 1, smt = false, right_angle = false, cutout = false, colour)``` | Draw pin header |
 | ```pin_socket(type, cols = 1, rows = 1, right_angle = false, height = 0, smt = false, cutout = false, colour)``` | Draw pin socket |
@@ -2392,11 +2487,18 @@ Pin headers and sockets, etc.
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
 |   1 | ```box_header(2p54header, 10, 2)``` |  Box header 10 x 2 |
+|   1 | ```box_header(2p54header, 8, 1)``` |  Box header 8 x 1 |
 |   1 | ```idc_transition(2p54header, 10)``` |  IDC transition header 10 x 2 |
 |   1 | ```pin_header(2p54header, 10, 2)``` |  Pin header 10 x 2 |
-|   1 | ```pin_header(2p54header, 10, 2, right_angle = true)``` |  Pin header 10 x 2 right_angle |
+|   1 | ```pin_header(2p54header, 3, 1, right_angle = true)``` |  Pin header 3 x 1 right_angle |
+|   1 | ```pin_header(2p54header, 3, 2, right_angle = true)``` |  Pin header 3 x 2 right_angle |
+|   1 | ```pin_header(2p54header, 3, 3, right_angle = true)``` |  Pin header 3 x 3 right_angle |
+|   1 | ```pin_header(2p54header, 8, 1)``` |  Pin header 8 x 1 |
 |   1 | ```pin_socket(2p54header, 10, 2)``` |  Pin socket 10 x 2 |
-|   1 | ```pin_socket(2p54header, 10, 2, right_angle = true)``` |  Pin socket 10 x 2 right_angle |
+|   1 | ```pin_socket(2p54header, 3, 1, right_angle = true)``` |  Pin socket 3 x 1 right_angle |
+|   1 | ```pin_socket(2p54header, 3, 2, right_angle = true)``` |  Pin socket 3 x 2 right_angle |
+|   1 | ```pin_socket(2p54header, 3, 3, right_angle = true)``` |  Pin socket 3 x 3 right_angle |
+|   1 | ```pin_socket(2p54header, 8, 1)``` |  Pin socket 8 x 1 |


 <a href="#top">Top</a>
@@ -2591,10 +2693,10 @@ Linear rails with carriages.
 ### Modules
 | Module | Description |
 |:--- |:--- |
-| ```carriage(type, rail, end_colour = grey20, wiper_colour = grey20)``` | Draw the specified carriage |
+| ```carriage(type, rail, end_colour = grey(20)``` | Draw the specified carriage |
 | ```carriage_hole_positions(type)``` | Position children over screw holes |
 | ```rail(type, length)``` | Draw the specified rail |
-| ```rail_assembly(type, length, pos, carriage_end_colour = grey20, carriage_wiper_colour = grey20)``` | Rail and carriage assembly |
+| ```rail_assembly(type, length, pos, carriage_end_colour = grey(20)``` | Rail and carriage assembly |
 | ```rail_hole_positions(type, length, first = 0, screws = 100, both_ends = true)``` | Position children over screw holes |
 | ```rail_screws(type, length, thickness, screws = 100)``` | Place screws in the rail |

@@ -2603,24 +2705,27 @@ Linear rails with carriages.
 ### Vitamins
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
-|   1 | ```rail(MGN15, 260)``` |  Linear rail MGN15 x 260mm |
+|   1 | ```rail(MGN12, 200)``` |  Linear rail MGN12 x 200mm |
+|   1 | ```rail(MGN12H, 200)``` |  Linear rail MGN12H x 200mm |
+|   1 | ```rail(MGN15, 200)``` |  Linear rail MGN15 x 200mm |
 |   1 | ```rail(MGN5, 200)``` |  Linear rail MGN5 x 200mm |
 |   1 | ```rail(MGN7, 200)``` |  Linear rail MGN7 x 200mm |
 |   1 | ```rail(MGN9, 200)``` |  Linear rail MGN9 x 200mm |
 |   1 | ```rail(SSR15, 200)``` |  Linear rail SSR15 x 200mm |
 |  26 | ```nut(M2_nut, nyloc = true)``` |  Nut M2 x 1.6mm nyloc |
-|  17 | ```nut(M3_nut, nyloc = true)``` |  Nut M3 x 2.4mm nyloc |
+|  31 | ```nut(M3_nut, nyloc = true)``` |  Nut M3 x 2.4mm nyloc |
 |   4 | ```nut(M4_nut, nyloc = true)``` |  Nut M4 x 3.2mm nyloc |
 |  11 | ```screw(M2_cap_screw, 10)``` |  Screw M2 cap x 10mm |
 |  15 | ```screw(M2_cs_cap_screw, 10)``` |  Screw M2 cs cap x 10mm |
 |   8 | ```screw(M3_cap_screw, 10)``` |  Screw M3 cap x 10mm |
-|   5 | ```screw(M3_cap_screw, 16)``` |  Screw M3 cap x 16mm |
+|  12 | ```screw(M3_cap_screw, 12)``` |  Screw M3 cap x 12mm |
+|   3 | ```screw(M3_cap_screw, 16)``` |  Screw M3 cap x 16mm |
 |   2 | ```screw(M3_cs_cap_screw, 12)``` |  Screw M3 cs cap x 12mm |
-|   2 | ```screw(M3_cs_cap_screw, 16)``` |  Screw M3 cs cap x 16mm |
+|   6 | ```screw(M3_cs_cap_screw, 16)``` |  Screw M3 cs cap x 16mm |
 |   2 | ```screw(M4_cap_screw, 16)``` |  Screw M4 cap x 16mm |
 |   2 | ```screw(M4_cs_cap_screw, 20)``` |  Screw M4 cs cap x 20mm |
 |  26 | ```washer(M2_washer)``` |  Washer  M2 x 5mm x 0.3mm |
-|  17 | ```washer(M3_washer)``` |  Washer  M3 x 7mm x 0.5mm |
+|  31 | ```washer(M3_washer)``` |  Washer  M3 x 7mm x 0.5mm |
 |   4 | ```washer(M4_washer)``` |  Washer  M4 x 9mm x 0.8mm |


@@ -2824,6 +2929,7 @@ Machine screws and wood screws with various head styles.
 |   1 | ```screw(No632_pan_screw, 30)``` |  Screw 6-32 pan x 30mm |
 |   1 | ```screw(M2_cap_screw, 10)``` |  Screw M2 cap x 10mm |
 |   1 | ```screw(M2_cs_cap_screw, 10)``` |  Screw M2 cs cap x 10mm |
+|   1 | ```screw(M2_dome_screw, 10)``` |  Screw M2 dome x 10mm |
 |   1 | ```screw(M2p5_cap_screw, 10)``` |  Screw M2.5 cap x 10mm |
 |   1 | ```screw(M2p5_pan_screw, 10)``` |  Screw M2.5 pan x 10mm |
 |   1 | ```screw(M3_cap_screw, 10)``` |  Screw M3 cap x 10mm |
@@ -3080,11 +3186,14 @@ Surface mount components for PCBs.
 |:--- |:--- |
 | ```smd_led_lens(type)``` | Lens length width and height |
 | ```smd_led_size(type)``` | Body length, width and height |
+| ```smd_res_end_cap(type)``` | End cap width |
+| ```smd_res_power(type)``` | Power rating in Watts |
+| ```smd_res_size(type)``` | Body length, width and height |

 ### Functions
 | Function | Description |
 |:--- |:--- |
-| ```smd_100th(x)``` | Convert dimesion to 1/100" notation |
+| ```smd_100th(x)``` | Convert dimension to 1/100" notation |
 | ```smd_led_height(type)``` | Total height |
 | ```smd_size(size)``` | Convert size to 1/100" notation |

@@ -3092,13 +3201,18 @@ Surface mount components for PCBs.
 | Module | Description |
 |:--- |:--- |
 | ```smd_led(type, colour, cutout)``` | Draw an SMD LED with specified ```colour``` |
+| ```smd_resistor(type, value)``` | Draw an SMD resistor with specified value |

 ![smds](tests/png/smds.png)

 ### Vitamins
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
-|   1 | ```smd_led(LED0805, green)``` |  SMD LED 0805 green |
+|   1 | ```smd_led(LED0603, green)``` |  SMD LED 0603 green |
+|   1 | ```smd_led(LED0805, blue)``` |  SMD LED 0805 blue |
+|   1 | ```smd_resistor(RES0603, 1R0)``` |  SMD resistor 0603 1R0 0.1W |
+|   1 | ```smd_resistor(RES0805, 10M)``` |  SMD resistor 0805 10M 0.125W |
+|   1 | ```smd_resistor(RES1206, 100K)``` |  SMD resistor 1206 100K 0.25W |


 <a href="#top">Top</a>
@@ -3516,10 +3630,15 @@ Tubing and sleeving. The internal diameter can be forced to stretch it over some
 | ```tubing_material(type)``` | Material description |
 | ```tubing_od(type)``` | Outside diameter |

+### Functions
+| Function | Description |
+|:--- |:--- |
+| ```tubing_or(type)``` | Outside radius |
+
 ### Modules
 | Module | Description |
 |:--- |:--- |
-| ```tubing(type, length = 15, forced_id = 0)``` | Draw specified tubing with optional forced internal diameter |
+| ```tubing(type, length = 15, forced_id = 0, center = true)``` | Draw specified tubing with optional forced internal diameter |

 ![tubings](tests/png/tubings.png)

@@ -3533,7 +3652,10 @@ Tubing and sleeving. The internal diameter can be forced to stretch it over some
 |   1 | ```tubing(NEOP85)``` |  Neoprene tubing OD 8mm ID 5mm x 15mm |
 |   1 | ```tubing(PTFE07)``` |  PTFE sleeving OD 1.2mm ID 0.71mm x 15mm |
 |   1 | ```tubing(PTFE20)``` |  PTFE sleeving OD 2.6mm ID 2mm x 15mm |
+|   1 | ```tubing(PTFE2_3)``` |  PTFE tubing OD 3mm ID 2mm x 15mm |
 |   1 | ```tubing(PF7)``` |  PTFE tubing OD 4.6mm ID 3.84mm x 15mm |
+|   1 | ```tubing(PTFE2_4)``` |  PTFE tubing OD 4mm ID 2mm x 15mm |
+|   1 | ```tubing(PTFE4_6)``` |  PTFE tubing OD 6mm ID 4mm x 15mm |
 |   1 | ```tubing(PVC64)``` |  PVC aquarium tubing OD 6mm ID 4mm x 15mm |
 |   1 | ```tubing(PVC85)``` |  PVC aquarium tubing OD 8mm ID 5mm x 15mm |

@@ -3872,6 +3994,7 @@ Normally the side sheets are the same type but they can be overridden individual
 | ```box_height(type)``` | Internal height |
 | ```box_screw(type)``` | Screw type to be used at the corners |
 | ```box_sheets(type)``` | Sheet type used for the sides |
+| ```box_shelf_screw(type)``` | Screw type to hold a shelf |
 | ```box_top_sheet(type)``` | Sheet type for the top |
 | ```box_wall(type)``` | Wall thickness of 3D parts |
 | ```box_width(type)``` | Internal width |
@@ -3879,7 +4002,7 @@ Normally the side sheets are the same type but they can be overridden individual
 ### Functions
 | Function | Description |
 |:--- |:--- |
-| ```box(screw, wall, sheets, top_sheet, base_sheet, size, feet = false)``` | Construct a property list for a box. |
+| ```box(screw, wall, sheets, top_sheet, base_sheet, size, feet = false, shelf_screw = M3_dome_screw)``` | Construct a property list for a box. |
 | ```box_bezel_height(type, bottom)``` | Bezel height for top or bottom |
 | ```box_corner_gap(type)``` | Gap between box_sheets at the corners to connect inside and outside profiles |
 | ```box_inset(type)``` | How much the bezel intrudes on the specified width and length, away from the corners |
@@ -3899,6 +4022,7 @@ Normally the side sheets are the same type but they can be overridden individual
 | ```box_corner_profile(type)``` | Generates the corner profile STL for 3D printing. |
 | ```box_corner_profile_2D(type)``` | The 2D shape of the corner profile. |
 | ```box_corner_profile_section(type, section, sections)``` | Generates interlocking sections of the corner profile to allow it to be taller than the printer |
+| ```box_corner_profile_sections(type, section, sections)``` | Generate four copies of a corner profile section |
 | ```box_front(type)``` | Default front, can be overridden to customise |
 | ```box_front_blank(type, sheet = false)``` | Generates a 2D template for the front sheet, ```sheet``` can be set to override the type |
 | ```box_left(type)``` | Default left side, can be overridden to customise |
@@ -3906,6 +4030,9 @@ Normally the side sheets are the same type but they can be overridden individual
 | ```box_right(type)``` | Default right side, can be overridden to customise |
 | ```box_right_blank(type, sheet = false)``` | Generates a 2D template for the right sheet, ```sheet``` can be set to override the type |
 | ```box_shelf_blank(type, sheet = false)``` | Generates a 2D template for a shelf sheet |
+| ```box_shelf_bracket(type, screw_positions, wall = undef)``` | Generates a shelf bracket, the first optional child is a 2D cutout and the second 3D cutouts |
+| ```box_shelf_bracket_section(type, rows, cols, x, y)``` | Generates sections of the shelf bracket to allow it to be bigger than the printer |
+| ```box_shelf_screw_positions(type, screw_positions, thickness = 0, wall = undef)``` | Place children at the shelf screw positions |
 | ```box_top(type)``` | Default top, can be overridden to customise |
 | ```box_top_blank(type)``` | Generates a 2D template for the top sheet |
 | ```grill(width, height, r = 1000, poly = false, h = 0)``` | A staggered array of 5mm holes to make grills in sheets. Can be constrained to be circular. Set ```poly``` ```true``` for printing, ```false``` for milling. |
@@ -4170,7 +4297,7 @@ Star washers can be omitted by setting ```star_washers``` to false.
 ### Vitamins
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
-|   3 | ```insert(F1BM)``` |  Heatfit insert M2 |
+|   3 | ```insert(F1BM2)``` |  Heatfit insert M2 |
 |   3 | ```insert(F1BM2p5)``` |  Heatfit insert M2.5 |
 |   3 | ```insert(F1BM3)``` |  Heatfit insert M3 |
 |   3 | ```insert(F1BM4)``` |  Heatfit insert M4 |
@@ -4332,7 +4459,7 @@ The ring spacing as well as the number of spokes can be specified, if zero a gas
 | ---:|:--- |
 |   1 | fan_guard_120.stl |
 |   1 | fan_guard_17.stl |
-|   1 | fan_guard_25.stl |
+|   1 | fan_guard_25.4.stl |
 |   1 | fan_guard_30.stl |
 |   1 | fan_guard_40.stl |
 |   1 | fan_guard_50.stl |
@@ -4390,7 +4517,7 @@ Star washers can be omitted by setting ```star_washers``` to false.
 ### Vitamins
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
-|   3 | ```insert(F1BM)``` |  Heatfit insert M2 |
+|   3 | ```insert(F1BM2)``` |  Heatfit insert M2 |
 |   3 | ```insert(F1BM2p5)``` |  Heatfit insert M2.5 |
 |   3 | ```insert(F1BM3)``` |  Heatfit insert M3 |
 |   3 | ```insert(F1BM4)``` |  Heatfit insert M4 |
@@ -4720,7 +4847,7 @@ It can also have printed feet on the base with the screws doubling up to hold th
 ### Vitamins
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
-|   4 | ```insert(F1BM)``` |  Heatfit insert M2 |
+|   4 | ```insert(F1BM2)``` |  Heatfit insert M2 |
 |   4 | ```insert(F1BM3)``` |  Heatfit insert M3 |
 |   4 | ```screw(M2_cap_screw, 6)``` |  Screw M2 cap x  6mm |
 |   3 | ```screw(M3_pan_screw, 6)``` |  Screw M3 pan x  6mm |
@@ -5150,6 +5277,53 @@ Rounded fillet for adding to corners.
 ![fillet](tests/png/fillet.png)


+<a href="#top">Top</a>
+
+---
+<a name="Gears"></a>
+## Gears
+Utilities for making involute gears.
+
+Formulas from <https://khkgears.net/new/gear_knowledge/gear_technical_reference/involute_gear_profile.html>
+<https://khkgears.net/new/gear_knowledge/gear_technical_reference/calculation_gear_dimensions.html>
+and <https://www.tec-science.com/mechanical-power-transmission/involute-gear/calculation-of-involute-gears/>
+
+```involute_gear_profile()``` returns a polygon that can have the bore and spokes, etc, subtracted from it before linear extruding it to 3D.
+Helical gears can be made using ```twist``` and bevel gears using ```scale``` parameters of ```linear_extrude()```.
+
+Gears with less than 19 teeth (when pressure angle is 20) are profile shifted to avoid undercutting the tooth root. 7 teeth is considered
+the practical minimum.
+
+The clearance between tip and root defaults to module / 6, but can be overridden by setting the ```clearance``` parameter.
+
+The origin of the rack is the left end of the pitch line and its width is below the pitch line. I.e. it does not include the addendum.
+
+```involute_worm_profile()``` returns a tooth profile that can be passed to ```thread()``` to make worms.
+
+
+[utils/gears.scad](utils/gears.scad) Implementation.
+
+[tests/gears.scad](tests/gears.scad) Code for this example.
+
+### Functions
+| Function | Description |
+|:--- |:--- |
+| ```centre_distance(m, z1, z2, pa = 20)``` | Calculate distance between centres taking profile shift into account |
+| ```involute(r, u)``` | Involute of circle radius r at angle u in radians |
+| ```involute_gear_od(m, z, pa = 20)``` | involute gear outside diameter given modulus, tooth count and pressure angle |
+| ```involute_rack_tooth_profile(m, pa = 20, clearance = undef)``` | Calculate rack tooth profile given module and pressure angle |
+| ```involute_worm_profile(m, pa = 20, clearance = undef)``` | Calculate worm profile suitable for passing to thread() |
+| ```profile_shift(z, pa)``` | Calculate profile shift for small gears |
+
+### Modules
+| Module | Description |
+|:--- |:--- |
+| ```involute_gear_profile(m, z, pa = 20, clearance = undef, steps = 20)``` | Calculate gear profile given module, number of teeth and pressure angle |
+| ```involute_rack_profile(m, z, w, pa = 20, clearance = undef)``` | Calculate rack profile given module, number of teeth and pressure angle |
+
+![gears](tests/png/gears.png)
+
+
 <a href="#top">Top</a>

 ---
@@ -5170,6 +5344,31 @@ Method to print holes in mid air. See <https://hydraraptor.blogspot.com/2014/03/
 ![hanging_hole](tests/png/hanging_hole.png)


+<a href="#top">Top</a>
+
+---
+<a name="Horiholes"></a>
+## Horiholes
+Utilities for depicting the staircase slicing of horizontal holes made with [`teardrop_plus()`](#teardrops), see <https://hydraraptor.blogspot.com/2020/07/horiholes-2.html>
+
+
+[utils/horiholes.scad](utils/horiholes.scad) Implementation.
+
+[tests/horiholes.scad](tests/horiholes.scad) Code for this example.
+
+### Functions
+| Function | Description |
+|:--- |:--- |
+| ```teardrop_plus_x(r, y, h)``` | Calculate the ordinate of a compensated teardrop given y and layer height. |
+
+### Modules
+| Module | Description |
+|:--- |:--- |
+| ```horihole(r, z, h = 0, center = true)``` | For making horizontal holes that don't need support material and are correct dimensions |
+
+![horiholes](tests/png/horiholes.png)
+
+
 <a href="#top">Top</a>

 ---
@@ -5211,12 +5410,22 @@ Maths utilities for manipulating vectors and matrices.
 | Function | Description |
 |:--- |:--- |
 | ```angle_between(v1, v2)``` | Return the angle between two vectors |
+| ```augment(m)``` | Augment a matrix by adding an identity matrix to the right |
+| ```degrees(radians)``` | Convert degrees to radians |
 | ```euler(R)``` | Convert a rotation matrix to a Euler rotation vector. |
 | ```identity(n, x = 1)``` | Construct an arbitrary size identity matrix |
+| ```invert(m)``` | Invert a matrix |
+| ```nearly_zero(x)``` | True if x is close to zero |
+| ```radians(degrees)``` | Convert radians to degrees |
 | ```reverse(v)``` | Reverse a vector |
+| ```rot2_z(a)``` | Generate a 2x2 matrix to rotate around z |
 | ```rot3_z(a)``` | Generate a 3x3 matrix to rotate around z |
 | ```rotate(a, v)``` | Generate a 4x4 rotation matrix, ```a``` can be a vector of three angles or a single angle around ```z```, or around axis ```v``` |
+| ```rowswap(m, i, j)``` | Swap two rows of a matrix |
 | ```scale(v)``` |  Generate a 4x4 matrix that scales by ```v```, which can be a vector of xyz factors or a scalar to scale all axes equally |
+| ```solve(m, i = 0, j = 0)``` | Solve each row ensuring diagonal is not zero |
+| ```solve_row(m, i)``` | Make diagonal one by dividing the row by it and subtract from other rows to make column zero |
+| ```sqr(x)``` | Square x |
 | ```transform(v, m)``` | Apply 4x4 transform to a 3 vector by extending it and cropping it again |
 | ```transform_points(path, m)``` | Apply transform to a path |
 | ```translate(v)``` | Generate a 4x4 translation matrix, ```v``` can be ```[x, y]```, ```[x, y, z]``` or ```z``` |
@@ -5225,6 +5434,11 @@ Maths utilities for manipulating vectors and matrices.
 | ```vec3(v)``` | Return a 3 vector with the first three elements of ```v``` |
 | ```vec4(v)``` | Return a 4 vector with the first three elements of ```v``` |

+### Modules
+| Module | Description |
+|:--- |:--- |
+| ```position_children(list, t)``` | Position children if they are on the Z = 0 plane when transformed by t |
+
 ![maths](tests/png/maths.png)


@@ -5419,6 +5633,8 @@ specify a chamfer angle.
 Threads are by default solid, so the male version is wrapped around a cylinder and the female inside a tube. This can be suppressed to just get the helix, for
 example to make a printed pot with a screw top lid.

+A left hand thread can be made by using mirror([0,1]).
+
 Threads with a typical 60 degree angle appear too bright with OpenSCAD's primitive lighting model as they face towards the lights more than the top and sides of
 a cylinder. To get around this a colour can be passed to thread that is used to colour the cylinder and then toned down to colour the helix.

@@ -5445,7 +5661,7 @@ Threads obey the $fn, $fa, $fs variables.
 |:--- |:--- |
 | ```female_metric_thread(d, pitch, length, center = true, top = -1, bot = -1, colour = undef)``` | Create female thread with metric profile |
 | ```male_metric_thread(d, pitch, length, center = true, top = -1, bot = -1, solid = true, colour = undef)``` | Create male thread with metric profile |
-| ```thread(dia, pitch, length, profile, center = true, top = -1, bot = -1, starts = 1, solid = true, female = false, colour = undef)``` | Create male or femail thread, ends can be tapered, chamfered or square |
+| ```thread(dia, pitch, length, profile, center = true, top = -1, bot = -1, starts = 1, solid = true, female = false, colour = undef)``` | Create male or female thread, ends can be tapered, chamfered or square |

 ![thread](tests/png/thread.png)

@@ -5593,6 +5809,7 @@ Global constants, functions and modules. This file is used directly or indirectl
 | ```inch(x)``` | Inch to mm conversion (For fractional inches, 'inch(1 + 7/8)' will work as expected.) |
 | ```m(x)``` | m to mm conversion |
 | ```mm(x)``` | Explicit mm specified |
+| ```no_point(str)``` | Replace decimal point in string with 'p' |
 | ```r2sides(r)``` | Replicates the OpenSCAD logic to calculate the number of sides from the radius |
 | ```r2sides4n(r)``` | Round up the number of sides to a multiple of 4 to ensure points land on all axes |
 | ```sqr(x)``` | Returns the square of ```x``` |
@@ -5725,6 +5942,9 @@ This ensures `hull` and `minkowski` results have the correct dimensions when sph
 For making horizontal holes that don't need support material.
 Small holes can get away without it, but they print better with truncated teardrops.

+Using teardrop_plus() or setting the plus option on other modules will elongate the teardrop vertically by the layer height, so when sliced the staircase tips
+do not intrude into the circle. See <https://hydraraptor.blogspot.com/2020/07/horiholes-2.html>
+

 [utils/core/teardrops.scad](utils/core/teardrops.scad) Implementation.

@@ -5733,12 +5953,12 @@ Small holes can get away without it, but they print better with truncated teardr
 ### Modules
 | Module | Description |
 |:--- |:--- |
-| ```semi_teardrop(h, r, d = undef, center = true, chamfer = 0)``` | A semi teardrop in the positive Y domain |
-| ```teardrop(h, r, center = true, truncate = true, chamfer = 0)``` | For making horizontal holes that don't need support material, set ```truncate = false``` to make traditional RepRap teardrops that don't even need bridging |
+| ```semi_teardrop(h, r, d = undef, center = true, chamfer = 0, plus = false)``` | A semi teardrop in the positive Y domain |
+| ```teardrop(h, r, center = true, truncate = true, chamfer = 0, plus = false)``` | For making horizontal holes that don't need support material, set ```truncate = false``` to make traditional RepRap teardrops that don't even need bridging |
 | ```teardrop_chamfer(h, center, chamfer)``` | Helper module for adding chamfer to a teardrop |
-| ```teardrop_plus(h, r, center = true, truncate = true, chamfer = 0)``` | Slightly bigger teardrop to allow for the 3D printing staircase effect |
-| ```tearslot(h, r, w, center = true, chamfer = 0)``` | A horizontal slot that doesn't need support material |
-| ```vertical_tearslot(h, r, l, center = true, chamfer = 0)``` | A vertical slot that doesn't need support material |
+| ```teardrop_plus(h, r, center = true, truncate = true, chamfer = 0)``` | Slightly elongated teardrop to allow for the 3D printing staircase effect |
+| ```tearslot(h, r, w, center = true, chamfer = 0, plus = false)``` | A horizontal slot that doesn't need support material |
+| ```vertical_tearslot(h, r, l, center = true, chamfer = 0, plus = false)``` | A vertical slot that doesn't need support material |

 ![teardrops](tests/png/teardrops.png)

--- a/scripts/plateup.py
+++ b/scripts/plateup.py
@@ -27,6 +27,7 @@ import c14n_stl
 from set_config import *
 from deps import *
 from shutil import copyfile
+import re

 source_dirs = { "stl" : "platters", "dxf" : "panels" }
 target_dirs = { "stl" : "printed",  "dxf" : "routed" }
@@ -38,43 +39,54 @@ def plateup(target, part_type, usage = None):
    top_dir = set_config(target, usage)
    parts_dir = top_dir + part_type + 's'
    target_dir = parts_dir + '/' + target_dirs[part_type]
-    source_dir = top_dir + source_dirs[part_type]
-    deps_dir = source_dir + "/deps"
-    if not os.path.isdir(source_dir):
-        return
-    if not os.path.isdir(target_dir):
-        os.makedirs(target_dir)
-    if not os.path.isdir(deps_dir):
-        os.makedirs(deps_dir)
+    source_dir1 = source_dirs[part_type]
+    source_dir2 = top_dir + source_dirs[part_type]
    #
-    # Decide which files to make
-    #
-    sources = [file for file in os.listdir(source_dir) if file.endswith('.scad')]
-    #
-    # Run OpenSCAD on the source files to make the targets
+    # Loop through source directories
    #
    used = []
-    for src in sources:
-        src_file = source_dir + '/' + src
-        part_file = target_dir + '/' + src[:-4] + part_type
-        dname = deps_name(deps_dir, src)
-        changed = check_deps(part_file, dname)
-        if changed:
-            print(changed)
-            openscad.run("-D$bom=1", "-d", dname, "-o", part_file, src_file)
-            if part_type == 'stl':
-                c14n_stl.canonicalise(part_file)
-            log_name = 'openscad.log'
-        else:
-            log_name = 'openscad.echo'
-            openscad.run_silent("-D$bom=1", "-o", log_name, src_file)
+    all_sources = []
+    for dir in [source_dir1, source_dir2]:
+        if not os.path.isdir(dir):
+            continue
+        if not os.path.isdir(target_dir):
+            os.makedirs(target_dir)
        #
-        # Add the files on the BOM to the used list
+        # Make the deps dir
        #
-        with open(log_name) as file:
-            for line in file.readlines():
-                if line.startswith('ECHO: "~') and line.endswith('.' + part_type + '"\n'):
-                    used.append(line[8:-2])
+        deps_dir = dir + "/deps"
+        if not os.path.isdir(deps_dir):
+            os.makedirs(deps_dir)
+        #
+        # Decide which files to make
+        #
+        sources = [file for file in os.listdir(dir) if file.endswith('.scad')]
+        all_sources += sources
+        #
+        # Run OpenSCAD on the source files to make the targets
+        #
+        for src in sources:
+            src_file = dir + '/' + src
+            part_file = target_dir + '/' + src[:-4] + part_type
+            dname = deps_name(deps_dir, src)
+            changed = check_deps(part_file, dname)
+            if changed:
+                print(changed)
+                openscad.run("-D$bom=1", "-d", dname, "-o", part_file, src_file)
+                if part_type == 'stl':
+                    c14n_stl.canonicalise(part_file)
+                log_name = 'openscad.log'
+            else:
+                log_name = 'openscad.echo'
+                openscad.run_silent("-D$bom=1", "-o", log_name, src_file)
+            #
+            # Add the files on the BOM to the used list
+            #
+            with open(log_name) as file:
+                for line in file.readlines():
+                    match = re.match(r'^ECHO: "~(.*?\.' + part_type + r').*"$', line)
+                    if match:
+                        used.append(match.group(1))
    #
    # Copy file that are not included
    #
@@ -90,7 +102,7 @@ def plateup(target, part_type, usage = None):
    #
    # Remove any cruft
    #
-    targets = [file[:-4] + part_type for file in sources]
+    targets = [file[:-4] + part_type for file in all_sources]
    for file in os.listdir(target_dir):
        if file.endswith('.' + part_type):
            if not file in targets and not file in copied:
--- a/tests/PCB.scad
+++ b/tests/PCB.scad
@@ -34,7 +34,7 @@ TMC2130 = ["TMC2130", "TMC2130",
    [
        [  10,  1,  0, "-2p54header", 8, 1 ,undef, "blue" ],
        [  10, 13,  0, "-2p54header", 8, 1],
-        [  12,  7,  0, "-chip", 6, 4, 1, grey20 ],
+        [  12,  7,  0, "-chip", 6, 4, 1, grey(20) ],
        // mock up a heat sink
        [  10,  7,  0, "block", 9, 9,  2, TMC2130HeatSinkColor ],
        [  10, 11,  0, "block", 9, 1, 11, TMC2130HeatSinkColor ],
@@ -58,14 +58,18 @@ test_pcb = ["TestPCB", "Test PCB",
    // components
    [
        [ 20, -5, 180, "trimpot10"],
-        [ 20, -15,  0, "trimpot10", true],
-        [ 10,  2,   0, "smd_led", LED0805, "red"],
+        [ 20, -15,  90, "trimpot10", true],
+        [ 10,  2,   90, "smd_led", LED0805, "red"],
+        [ 13,  2,   90, "smd_led", LED0603, "orange"],
+        [ 16,  2,   90, "smd_res", RES1206, "1K"],
+        [ 19,  2,   90, "smd_res", RES0805, "1K"],
+        [ 22,  2,   90, "smd_res", RES0603, "1K"],
        [ 10,  10,   0, "2p54header", 4, 1],
        [ 25,  10,   0, "2p54header", 5, 1, false, "blue" ],
        [ 10,  20,   0, "2p54boxhdr", 4, 2],
        [ 10,  30,   0, "2p54socket", 6, 1],
        [ 25,  30,   0, "2p54socket", 4, 1, false, 0, false, "red" ],
-        [ 10,  40,   0, "chip", 10, 5, 1, grey20],
+        [ 10,  40,   0, "chip", 10, 5, 1, grey(20)],
        [  5,  50,   0, "led", LED3mm, "red"],
        [ 12,  50,   0, "led", LED5mm, "orange"],
        [ 25,  50,   0, "led", LED10mm, "yellow"],
@@ -82,22 +86,26 @@ test_pcb = ["TestPCB", "Test PCB",
        [  5, 218, 180, "hdmi"],
        [  3, 235, 180, "mini_hdmi"],
        [  6, 175, 180, "uSD", [12, 11.5, 1.4]],
+
+        [ 65,   9,   0, "link", inch(0.4)],
        [ 65,  12,   0, "ax_res", res1_8, 1000],
        [ 65,  17,   0, "ax_res", res1_4, 10000],
        [ 65,  22,   0, "ax_res", res1_2, 100000],

+        [ 80,   9,   0, "link", inch(0.2), inch(0.4)],
        [ 80,  12,   0, "ax_res", res1_8, 1000000, 1, inch(0.1)],
        [ 80,  17,   0, "ax_res", res1_4, 100,     2, inch(0.1)],
        [ 80,  22,   0, "ax_res", res1_2, 10,     10, inch(0.2)],

        [ 60,   3,   0, "flex"],
-        [ 50,  15,   0, "flat_flex"],
+        [ 50,  15, -90, "flat_flex"],
+        [ 40,  15, -90, "flat_flex", true],
        [ 60,  35,   0, "D_plug", DCONN9],

        [ 50,  50,   0, "molex_hdr", 2],
        [ 50,  60,   0, "jst_xh", 2],
        [ 50,  70, 180, "term254", 3],
-        [ 63,  70, 180, "term254", 3, undef, grey20],
+        [ 63,  70, 180, "term254", 3, undef, grey(20)],
        [ 75,  70, 180, "gterm508",2, undef, "blue"],

        [ 50,  90, 180, "gterm35", 4, [1,2]],
@@ -107,7 +115,7 @@ test_pcb = ["TestPCB", "Test PCB",

        [ 55, 110, 180, "gterm635", 2],
        [ 75, 110, 180, "gterm635", 2, undef, "blue"],
-        [ 90, 110, 180, "gterm", gt_5x17, 2, undef, grey20],
+        [ 90, 110, 180, "gterm", gt_5x17, 2, undef, grey(20)],

        [ 50, 130, 180, "term35", 4],
        [ 70, 130, 180, "term35", 3, "lime"],
--- a/tests/SMDs.scad
+++ b/tests/SMDs.scad
@@ -21,9 +21,14 @@ use <../utils/layout.scad>

 include <../vitamins/smds.scad>

-module smds()
-    layout([for(l = smd_leds) smd_led_size(l).x], 1)
-        smd_led(smd_leds[$i], ["green", "blue", "red"][$i % 3]);
+module smds() {
+    layout([for(r = smd_resistors) smd_res_size(r).x], 1)
+        smd_resistor(smd_resistors[$i], ["1R0", "10M", "100K"][$i % 3]);
+
+    translate([0, 3])
+        layout([for(l = smd_leds) smd_led_size(l).x], 1)
+            smd_led(smd_leds[$i], ["green", "blue", "red"][$i % 3]);
+}

 if($preview)
    smds();
--- a/tests/belts.scad
+++ b/tests/belts.scad
@@ -60,12 +60,12 @@ module belt_test() {
             [p4.x, p4.y, pulley_pr(GT2x20ob_pulley)]
           ];
    belt = GT2x6;
-    belt(belt, path, 80, [0,  belt_pitch_height(belt) - belt_thickness(belt) / 2]);
+    belt(belt, path, 80, [0,  0]);

    translate([-25, 0])
        layout([for(b = belts) belt_width(b)], 10)
            rotate([0, 90, 0])
-                belt(belts[$i], [[0, 0, 20], [0, 1, 20]], belt_colour = $i%2==0 ? grey90 : grey20, tooth_colour = $i%2==0 ? grey70 : grey50);
+                belt(belts[$i], [[0, 0, 20], [0, 1, 20]], belt_colour = $i%2==0 ? grey(90) : grey(20), tooth_colour = $i%2==0 ? grey(70) : grey(50));
 }

 if($preview)
--- a/tests/cameras.scad
+++ b/tests/cameras.scad
@@ -0,0 +1,31 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+include <../core.scad>
+use <../utils/layout.scad>
+
+include <../vitamins/cameras.scad>
+
+use <../vitamins/pcb.scad>
+
+module cameras()
+    layout([for(c = cameras) pcb_length(camera_pcb(c))], 10, false) let(c = cameras[$i])
+        camera(c);
+
+if($preview)
+    cameras();
--- a/tests/gears.scad
+++ b/tests/gears.scad
@@ -0,0 +1,66 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+include <../utils/core/core.scad>
+use <../utils/gears.scad>
+
+// left gear teeth
+z1 = 39; // [7 : 1 : 99]
+
+// Right gear teeth
+z2 = 7; // [7 : 1 : 99]
+
+//  Modulus
+m = 2.0; // [0.1 : 0.1 : 5.0]
+
+// Pressure angle
+pa = 20; // [14.5, 20, 22.5, 25]
+
+$show_numbers = false;
+
+module gears() {
+    color(pp1_colour)
+        rotate(-$t * 360)
+            linear_extrude(eps, center = true, convexity = z1)
+                difference() {
+                    involute_gear_profile(m, z1, pa);
+
+                    circle(r = m * z1 / 10);
+                }
+
+    color(pp2_colour)
+        translate([centre_distance(m, z1, z2, pa), 0])
+            rotate(180 + 180 / z2 + $t * 360 * z1 / z2)
+               linear_extrude(eps, center = true, convexity = z2)
+                    difference() {
+                         involute_gear_profile(m, z2, pa);
+
+                         circle(r = m * z2 / 10);
+                    }
+
+    z3 = floor((z1 + z2) / PI);
+    angle = -$t * 360 + 90 - floor(z1 / 4) * 360 / z1; // Line up the rack 1/4 turn around the gear
+    pitch = m * PI;
+    color(pp3_colour)
+        translate([(angle % ((z3 / z1) * 360)) / 360 * z1 * pitch, -centre_distance(m, z1, 0, pa)])
+            linear_extrude(eps, center = true)
+                involute_rack_profile(m, z3, 3 * m, pa);
+}
+
+rotate(is_undef($bom) ? 0 : [70, 0, 315])
+    gears();
--- a/tests/horiholes.scad
+++ b/tests/horiholes.scad
@@ -0,0 +1,90 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+$layer_height = 0.25;
+include <../utils/core/core.scad>
+use <../utils/horiholes.scad>
+
+show_disc = true;
+use_horihole = true;
+thickness = 6;
+length = 60;
+height = 20;
+overlap_x = 15;
+overlap_y = 10;
+
+module hole_positions() {
+    x0 = (length - 40) / 2;
+    for($i = [0 : 4], $z = 5 + $i * layer_height / 5, $r = 3)
+        translate([x0 + $i * 10, $z])
+            children();
+
+    for($i = [0 : 4], $z = 15 + $i * layer_height / 5, $r = 0.5 + $i / 2)
+        translate([x0 + $i * 10, $z])
+            children();
+}
+
+module horiholes_stl(t = thickness) {
+    rotate([90, 0, 0])
+        difference() {
+            linear_extrude(t, center = true) {
+                difference() {
+                    square([length, height]);
+
+                    hole_positions()
+                        if(use_horihole)
+                            horihole($r, $z);
+                        else
+                            teardrop_plus(h = 0, r = $r);
+                }
+            }
+        }
+    if(t == thickness)
+        translate([length / 2, 0])
+            rounded_rectangle([length + 2 * overlap_x, thickness + 2 * overlap_y, 2], 5);
+}
+
+module horiholes() {
+    stl_colour(pp1_colour)
+        rotate([-90, 0, 0])
+            horiholes_stl(eps);
+
+    if(show_disc)
+        hole_positions()
+            color(silver)
+                cylinder(r = $r, h = eps, center = true, $fn = 360);
+
+    hole_positions()
+        color("red")
+            linear_extrude(2 * eps, center = true)
+                intersection() {
+                    difference() {
+                        square(8, center = true);
+
+                        horihole($r, $z);
+                    }
+
+                    circle($r, $fn = 360);
+                }
+}
+
+if($preview)
+    rotate(is_undef($bom) ? 0 : [70, 0, 315])
+        horiholes();
+else
+    horiholes_stl();
--- a/tests/magnets.scad
+++ b/tests/magnets.scad
@@ -0,0 +1,29 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+include <../core.scad>
+use <../utils/layout.scad>
+
+include <../vitamins/magnets.scad>
+
+module magnets()
+    layout([for(m = magnets) magnet_od(m)], 5)
+        magnet(magnets[$i]);
+
+if($preview)
+    magnets();
--- a/tests/pin_headers.scad
+++ b/tests/pin_headers.scad
@@ -23,26 +23,53 @@ include <../vitamins/pin_headers.scad>

 pins = 10;

-module pin_headers()
+module pin_headers() {
    layout([for(p = pin_headers) hdr_pitch(p) * pins], 15) {
        idc_transition(pin_headers[$i], 10);

        translate([0, 20])
-            pin_header(pin_headers[$i], 10, 2, right_angle = true);
+            pin_header(pin_headers[$i], 3, 2, right_angle = true);
+
+        translate([-10, 20])
+            pin_header(pin_headers[$i], 3, 1, right_angle = true);
+
+         translate([10, 20])
+            pin_header(pin_headers[$i], 3, 3, right_angle = true);
+
+        translate([0, 30])
+            pin_header(pin_headers[$i], 8, 1);

        translate([0, 40])
            pin_header(pin_headers[$i], 10, 2);

+        translate([0, 50])
+            box_header(pin_headers[$i], 8, 1);
+
        translate([0, 60])
            box_header(pin_headers[$i], 10, 2);

+        translate([0, 70])
+            pin_socket(pin_headers[$i], 8, 1);
+
        translate([0, 80])
            pin_socket(pin_headers[$i], 10, 2);

-        translate([0, 110])
-            pin_socket(pin_headers[$i], 10, 2, right_angle = true);
+        translate([-10, 105])
+            pin_socket(pin_headers[$i], 3, 1, right_angle = true);

+        translate([0, 105])
+            pin_socket(pin_headers[$i], 3, 2, right_angle = true);
+
+        translate([10, 105])
+            pin_socket(pin_headers[$i], 3, 3, right_angle = true);
    }

+    translate([-20, 0])
+        jst_xh_header(jst_xh_header, 5);
+
+    translate([-20, 20])
+        jst_xh_header(jst_xh_header, 5, true);
+}
+
 if($preview)
    pin_headers();
--- a/tests/png/ball_bearings.png
+++ b/tests/png/ball_bearings.png
--- a/tests/png/belts.png
+++ b/tests/png/belts.png
--- a/tests/png/box.png
+++ b/tests/png/box.png
--- a/tests/png/cameras.png
+++ b/tests/png/cameras.png
--- a/tests/png/corner_block.png
+++ b/tests/png/corner_block.png
--- a/tests/png/door_hinge.png
+++ b/tests/png/door_hinge.png
--- a/tests/png/fan_guard.png
+++ b/tests/png/fan_guard.png
--- a/tests/png/fans.png
+++ b/tests/png/fans.png
--- a/tests/png/fixing_block.png
+++ b/tests/png/fixing_block.png
--- a/tests/png/flat_hinge.png
+++ b/tests/png/flat_hinge.png
--- a/tests/png/gears.png
+++ b/tests/png/gears.png
--- a/tests/png/horiholes.png
+++ b/tests/png/horiholes.png
--- a/tests/png/hot_ends.png
+++ b/tests/png/hot_ends.png
--- a/tests/png/kp_pillow_blocks.png
+++ b/tests/png/kp_pillow_blocks.png
--- a/tests/png/light_strips.png
+++ b/tests/png/light_strips.png
--- a/tests/png/magnets.png
+++ b/tests/png/magnets.png
--- a/tests/png/modules.png
+++ b/tests/png/modules.png
--- a/tests/png/pcb.png
+++ b/tests/png/pcb.png
--- a/tests/png/pcbs.png
+++ b/tests/png/pcbs.png
--- a/tests/png/pin_headers.png
+++ b/tests/png/pin_headers.png
--- a/tests/png/rails.png
+++ b/tests/png/rails.png
--- a/tests/png/ring_terminals.png
+++ b/tests/png/ring_terminals.png
--- a/tests/png/screws.png
+++ b/tests/png/screws.png
--- a/tests/png/smds.png
+++ b/tests/png/smds.png
--- a/tests/png/teardrops.png
+++ b/tests/png/teardrops.png
--- a/tests/png/thread.png
+++ b/tests/png/thread.png
--- a/tests/png/tubings.png
+++ b/tests/png/tubings.png
--- a/tests/png/veroboard.png
+++ b/tests/png/veroboard.png
--- a/tests/png/wire.png
+++ b/tests/png/wire.png
--- a/tests/printed_box.scad
+++ b/tests/printed_box.scad
@@ -67,7 +67,7 @@ module box1_external_additions() {

 module box1_holes() {
    box1_feet_positions()
-        teardrop(r = screw_pilot_hole(foot_screw(foot)), h = 10, center = true);
+        teardrop_plus(r = screw_pilot_hole(foot_screw(foot)), h = 10, center = true);
 }


--- a/tests/rails.scad
+++ b/tests/rails.scad
@@ -25,15 +25,15 @@ use <../vitamins/nut.scad>
 sheet = 3;

 module rails()
-    layout([for(l = rails) carriage_width(rail_carriage(l))], 25)
+    layout([for(l = rails) carriage_width(rail_carriage(l))], 20)
        rotate(-90) {
            rail = rails[$i];
-            length = rail == MGN15 ? 260 : 200;
+            length = 200;
            screw = rail_screw(rail);
            nut = screw_nut(screw);
            washer = screw_washer(screw);

-            rail_assembly(rail, length, rail_travel(rail, length) / 2, $i<2 ? grey20 : "green", $i<2 ? grey20 : "red");
+            rail_assembly(rail, length, rail_travel(rail, length) / 2, $i<2 ? grey(20) : "green", $i<2 ? grey(20) : "red");

            rail_screws(rail, length, sheet + nut_thickness(nut, true) + washer_thickness(washer));

--- a/tests/teardrops.scad
+++ b/tests/teardrops.scad
@@ -41,7 +41,10 @@ module teardrops() {

                        translate([20, 10])
                            semi_teardrop(h = 0, r = 3);
-                    }
+
+                        translate([20, 20])
+                            teardrop(h = 0, r = 3, truncate = false, plus = true);
+                   }
                }
                translate([40, 0, 1.5]) {
                    h = 3 + eps;
@@ -61,6 +64,9 @@ module teardrops() {

                    translate([20, 10])
                        semi_teardrop(h = h, r = 3, chamfer = chamfer);
+
+                    translate([20, 20])
+                        teardrop(h = h, r = 3, truncate = false, plus = false, chamfer = chamfer);
                }
            }
 }
--- a/tests/thread.scad
+++ b/tests/thread.scad
@@ -26,27 +26,27 @@ profile = thread_profile(pitch / 2, pitch * 0.366, 30);

 module threads()
    for(female = [false, true]) translate([0, female ? -20 : 0]) {
-    length = female ? 8  : 40;
-    dia = female ? 8 : 8 - pitch;
-    colour = female ? brass : silver;
+        length = female ? 8  : 40;
+        dia = female ? 8 : 8 - pitch;
+        colour = female ? brass : silver;

-    thread(dia, starts * pitch, length, profile, starts = starts, top = 45, bot = 45, female = female, colour = colour);
+        thread(dia, starts * pitch, length, profile, starts = starts, top = 45, bot = 45, female = female, colour = colour);

-    color(colour)
-        translate([20, 0])
-            thread(dia, starts * pitch, length, profile, starts = starts, top = 0, bot = 0, female = female);
+        color(colour)
+            translate([20, 0])
+                thread(dia, starts * pitch, length, profile, starts = starts, top = 0, bot = 0, female = female);

-    translate([40, 0])
-        thread(dia, starts * pitch, length, profile, starts = starts, top = -1, bot = -1, female = female, colour = colour);
+        translate([40, 0])
+            thread(dia, starts * pitch, length, profile, starts = starts, top = -1, bot = -1, female = female, colour = colour);

-    color(colour)
-        translate([60, 0])
-            thread(dia, 2 * pitch, length, profile, starts = 2, top = -1, bot = -1, female = female);
+        color(colour)
+            translate([60, 0])
+                thread(dia, 2 * pitch, length, profile, starts = 2, top = -1, bot = -1, female = female);

-    color(colour)
-        translate([80, 0])
-            thread(dia, pitch, length, profile, starts = 1, top = -1, bot = -1, female = female);
-}
+        color(colour)
+            translate([80, 0])
+                thread(dia, pitch, length, profile, starts = 1, top = -1, bot = -1, female = female);
+    }

 let($show_threads = true)
    threads();
--- a/utils/core/core.scad
+++ b/utils/core/core.scad
@@ -28,12 +28,12 @@ use <global.scad>

 module use_stl(name) {               //! Import an STL to make a build platter
    stl(name);
-
-    import(str("../stls/", name, ".stl"));
+    path = is_undef($target) ? "../stls/" : str("../", $target, "/stls/");
+    import(str(path, name, ".stl"));
 }

 module use_dxf(name) {               //! Import a DXF to make a build panel
    dxf(name);
-
-    import(str("../dxfs/", name, ".dxf"));
+    path = is_undef($target) ? "../dxfs/" : str("../", $target, "/dxfs/");
+    import(str(path, name, ".dxf"));
 }
--- a/utils/core/global.scad
+++ b/utils/core/global.scad
@@ -31,6 +31,7 @@ function m(x)    = x * 1000.0;

 function sqr(x) = x * x;                                                            //! Returns the square of ```x```
 function echoit(x) = echo(x) x;                                                     //! Echo expression and return it, useful for debugging
+function no_point(str) = chr([for(c = str(str)) if(c == ".") ord("p") else ord(c)]);//! Replace decimal point in string with 'p'
 function in(list, x) = !!len([for(v = list) if(v == x) true]);                      //! Returns true if ```x``` is an element in the ```list```
 function Len(x) = is_list(x) ? len(x) : 0;                                          //! Returns the length of a list or 0 if ```x``` is not a list
 function r2sides(r) = $fn ? $fn : ceil(max(min(360/ $fa, r * 2 * PI / $fs), 5));    //! Replicates the OpenSCAD logic to calculate the number of sides from the radius
--- a/utils/core/teardrops.scad
+++ b/utils/core/teardrops.scad
@@ -20,17 +20,32 @@
 //
 //! For making horizontal holes that don't need support material.
 //! Small holes can get away without it, but they print better with truncated teardrops.
+//!
+//! Using teardrop_plus() or setting the plus option on other modules will elongate the teardrop vertically by the layer height, so when sliced the staircase tips
+//! do not intrude into the circle. See <https://hydraraptor.blogspot.com/2020/07/horiholes-2.html>
 //
-module teardrop(h, r, center = true, truncate = true, chamfer = 0) { //! For making horizontal holes that don't need support material, set ```truncate = false``` to make traditional RepRap teardrops that don't even need bridging
+module teardrop(h, r, center = true, truncate = true, chamfer = 0, plus = false) { //! For making horizontal holes that don't need support material, set ```truncate = false``` to make traditional RepRap teardrops that don't even need bridging
    module teardrop_2d(r, truncate) {
-        hull() {
-            circle4n(r);
-            if(truncate)
-                translate([0, r / 2])
-                    square([2 * r * (sqrt(2) - 1), r], center = true);
-            else
-                polygon([[0, 0], [eps, 0], [0, r * sqrt(2)]]);
-        }
+        er = layer_height / 2 - eps;    // Extrustion edge radius
+        R = plus ? r + er : r;          // Corrected radius
+        offset = plus ? -er : 0;        // Offset inwards
+        hull()
+            for(side = [0 : 1])
+                mirror([side, 0, 0])
+                    intersection() {
+                        hull()
+                        translate([offset, 0]) {
+                            circle4n(R);
+
+                            if(truncate)
+                                translate([0, R / 2])
+                                    square([2 * R * (sqrt(2) - 1), R], center = true);
+                            else
+                                polygon([[0, 0], [eps, 0], [0, R * sqrt(2)]]);
+                        }
+                        translate([0, -2 * R])
+                            square([R, 4 * R]);
+                    }
    }

    render(convexity = 5)
@@ -40,23 +55,23 @@ module teardrop(h, r, center = true, truncate = true, chamfer = 0) { //! For mak
    teardrop_chamfer(h, center, chamfer) {
        linear_extrude(eps, center = true)
            teardrop_2d(r + chamfer / 2, truncate);
+
        translate_z(-chamfer / 2)
            linear_extrude(eps, center = true)
                teardrop_2d(r, truncate);
    }
 }

-module semi_teardrop(h, r, d = undef, center = true, chamfer = 0) { //! A semi teardrop in the positive Y domain
-    module semi_teardrop_2d(r, d) {
+module semi_teardrop(h, r, d = undef, center = true, chamfer = 0, plus = false) { //! A semi teardrop in the positive Y domain
+    module semi_teardrop_2d(r, d)
        intersection() {
            R = is_undef(d) ? r : d / 2;
-            teardrop(r = R, h = 0);
+            teardrop(r = R, h = 0, plus = plus);

            sq = R + 1;
            translate([-sq, 0])
                square([2 * sq, sq]);
        }
-    }

    render(convexity = 5)
        extrude_if(h, center)
@@ -65,22 +80,21 @@ module semi_teardrop(h, r, d = undef, center = true, chamfer = 0) { //! A semi t
    teardrop_chamfer(h, center, chamfer) {
        linear_extrude(eps, center = true)
            semi_teardrop_2d(r + chamfer / 2, d);
+
        translate_z(-chamfer / 2)
            linear_extrude(eps, center = true)
                semi_teardrop_2d(r, d);
    }
 }

-module teardrop_plus(h, r, center = true, truncate = true, chamfer = 0) //! Slightly bigger teardrop to allow for the 3D printing staircase effect
-    teardrop(h, r + layer_height / 4, center, truncate, chamfer);
+module teardrop_plus(h, r, center = true, truncate = true, chamfer = 0) //! Slightly elongated teardrop to allow for the 3D printing staircase effect
+    teardrop(h, r, center, truncate, chamfer, plus = true);

-module tearslot(h, r, w, center = true, chamfer = 0) { //! A horizontal slot that doesn't need support material
-    module tearslot_2d(r, w) {
-        hull() {
-            translate([-w / 2, 0]) teardrop(r = r, h = 0);
-            translate([w / 2, 0]) teardrop(r = r, h = 0);
-        }
-    }
+module tearslot(h, r, w, center = true, chamfer = 0, plus = false) { //! A horizontal slot that doesn't need support material
+    module tearslot_2d(r, w)
+        hull()
+            for(x = [-1, 1])
+                translate([x * w / 2, 0]) teardrop(r = r, h = 0, plus = plus);

    extrude_if(h, center)
        tearslot_2d(r, w);
@@ -88,19 +102,19 @@ module tearslot(h, r, w, center = true, chamfer = 0) { //! A horizontal slot tha
    teardrop_chamfer(h, center, chamfer) {
        linear_extrude(eps, center = true)
            tearslot_2d(r + chamfer / 2, w);
+
        translate_z(-chamfer / 2)
            linear_extrude(eps, center = true)
                tearslot_2d(r, w);
    }
 }

-module vertical_tearslot(h, r, l, center = true, chamfer = 0) { //! A vertical slot that doesn't need support material
-    module vertical_tearslot_2d(r, l) {
-        hull() {
-            translate([0,  l / 2]) teardrop(0, r, true);
-            translate([0, -l / 2]) circle4n(r);
-        }
-    }
+module vertical_tearslot(h, r, l, center = true, chamfer = 0, plus = false) { //! A vertical slot that doesn't need support material
+    module vertical_tearslot_2d(r, l)
+        hull()
+            for(y = [-1, 1])
+                translate([0,  y * l / 2])
+                    teardrop(0, r, true, plus = plus);

    extrude_if(h, center)
        vertical_tearslot_2d(r, l);
@@ -108,6 +122,7 @@ module vertical_tearslot(h, r, l, center = true, chamfer = 0) { //! A vertical s
    teardrop_chamfer(h, center, chamfer) {
        linear_extrude(eps, center = true)
            vertical_tearslot_2d(r + chamfer / 2, l);
+
        translate_z(-chamfer / 2)
            linear_extrude(eps, center = true)
                vertical_tearslot_2d(r, l);
@@ -123,4 +138,3 @@ module teardrop_chamfer(h, center, chamfer) { //! Helper module for adding chamf
                        hull()
                            children();
 }
-
--- a/utils/gears.scad
+++ b/utils/gears.scad
@@ -0,0 +1,138 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+
+//
+//! Utilities for making involute gears.
+//!
+//! Formulas from <https://khkgears.net/new/gear_knowledge/gear_technical_reference/involute_gear_profile.html>
+//! <https://khkgears.net/new/gear_knowledge/gear_technical_reference/calculation_gear_dimensions.html>
+//! and <https://www.tec-science.com/mechanical-power-transmission/involute-gear/calculation-of-involute-gears/>
+//!
+//! ```involute_gear_profile()``` returns a polygon that can have the bore and spokes, etc, subtracted from it before linear extruding it to 3D.
+//! Helical gears can be made using ```twist``` and bevel gears using ```scale``` parameters of ```linear_extrude()```.
+//!
+//! Gears with less than 19 teeth (when pressure angle is 20) are profile shifted to avoid undercutting the tooth root. 7 teeth is considered
+//! the practical minimum.
+//!
+//! The clearance between tip and root defaults to module / 6, but can be overridden by setting the ```clearance``` parameter.
+//!
+//! The origin of the rack is the left end of the pitch line and its width is below the pitch line. I.e. it does not include the addendum.
+//!
+//! ```involute_worm_profile()``` returns a tooth profile that can be passed to ```thread()``` to make worms.
+//
+include <core/core.scad>
+use <maths.scad>
+
+function involute(r, u) = let(a = degrees(u), c = cos(a), s = sin(a)) r * [c + u * s, s - u * c]; //! Involute of circle radius r at angle u in radians
+
+function profile_shift(z, pa) = z ? max(1 - z * sqr(sin(pa)) / 2, 0) : 0; //! Calculate profile shift for small gears
+
+function centre_distance(m, z1, z2, pa = 20) = //! Calculate distance between centres taking profile shift into account
+    let(x1 = profile_shift(z1, pa), x2 = profile_shift(z2, pa)) m * (z1/2 + z2/2 + x1 + x2);
+
+function involute_gear_od(m, z, pa = 20) = //! involute gear outside diameter given modulus, tooth count and pressure angle
+    m * (z + 2 * profile_shift(z, pa) + 2);
+
+module involute_gear_profile(m, z, pa = 20, clearance = undef, steps = 20) { //! Calculate gear profile given module, number of teeth and pressure angle
+    assert(z >= 7, "Gears must have at least 7 teeth.");
+    d = m * z;                                                  // Reference pitch circle diameter
+    x = profile_shift(z, pa);                                   // Profile shift
+    c = is_undef(clearance) ? m / 6 : clearance;                // Clearance from tip to root
+
+    base_d = d * cos(pa);                                       // Base diameter
+    root_r = d / 2 + m * (x - 1) - c;                           // Root radius (dedendum circle radius)
+    tip_d = d + 2 * m * (1 + x);                                // Tip diameter (addendum circle diameter)
+    tpa = acos(base_d / tip_d);                                 // Tip pressure angle
+    inva = tan(pa) - radians(pa);                               // Involute alpha
+    invaa = tan(tpa) - radians(tpa);                            // Involute alphaa
+    ta =  PI / (2 * z) + 2 * x * tan(pa) / z + inva - invaa;    // Tooth tip thickness angle, radians
+    crest_w = ta * tip_d;                                       // Crest width
+    umax = sqrt(sqr(tip_d / base_d) - 1);                       // Max value of the involute parameter
+
+    base_r = base_d / 2;
+    p1 = involute(base_r, 0);
+    p2 = involute(base_r, umax);
+    dist = norm(p2 - p1);                                       // distance between beginning and end of the involute curve
+
+    base_angle = 2 * acos((sqr(base_r) + sqr(tip_d / 2) - sqr(dist)) / base_r / tip_d) + degrees(2 * ta);
+    root_angle = 360 / z - base_angle;
+    root_circle_r = base_r * sin(root_angle / 2);
+
+    if(!is_undef($show_numbers) && $show_numbers) {
+        echo(d=d);
+        echo(base_d=base_d);
+        echo(tip_d=tip_d);
+        echo(tpa = tpa);
+        echo(inva=inva);
+        echo(invaa=invaa);
+        echo(x=x);
+        echo(ta=ta);
+        echo(crest_w=crest_w);
+        echo(umax = umax);
+        echo(base_angle=base_angle);
+        echo(root_angle=root_angle);
+    }
+    involute = [for(i = [0 : steps], u = umax * i / steps) involute(base_r, u)]; // involute for the bottom side of the tooth
+    truncated = [for(p = involute) if((rot2_z(-base_angle / 2) * p).y <= 0) p];  // removed any above the centreline to prevent overlap
+    reflection = reverse([for(p = truncated) rot2_z(base_angle) * [p.x, -p.y] ]); // reflect and rotate to make the top edge
+
+    root = reverse([for(a = [90 : 180 / steps : 270]) rot2_z(base_angle + root_angle / 2) * ([base_r, 0] + root_circle_r * [cos(a), sin(a)]) ]);
+    tooth = concat(truncated, reflection, root);
+    gear = concat([for(i = [0 : z - 1], p = tooth) rot2_z(i * 360 / z) * p]);
+    rotate(-base_angle / 2)
+        union() {
+            polygon(gear);
+
+            circle(root_r);
+        }
+}
+
+function involute_rack_tooth_profile(m, pa = 20, clearance = undef) = //! Calculate rack tooth profile given module and pressure angle
+    let(p = PI * m,                                     // Pitch
+        ha = m,                                         // Addendum
+        c = is_undef(clearance) ? m / 4 : clearance,    // Tip root clearance
+        hf = m + c,                                     // Dedendum
+        hw = 2 * m,                                     // Working depth
+        h = ha + hf,                                    // Tooth depth
+        crest_w = p / 2 - 2 * ha * tan(pa),             // Crest width
+        base_w = crest_w + 2 * hw * tan(pa),            // Base width
+        root_w = p - base_w,                            // Root width
+        clearance_w = root_w - 2 * c * tan(pa),         // Width of clearance without fillet
+        kx = tan(pa / 2 + 45),                          // Fillet ratio of radius and xoffset
+        pf = min(0.38 * m, kx * clearance_w / 2),       // Dedendum fillet radius
+        x = pf / kx,                                    // Fillet centre x offset from corner
+        sides = ceil(r2sides(pf) * (90 - pa) / 360),    // Fillet facets taking $fa, $fs and $fn into account
+        fillet = [ for(i = [0 : sides - 1], a = i * (90 - pa) / sides + 270) [clearance_w / 2 - x,  -hf + pf] + pf * [cos(a), sin(a)] ],
+        reflection = reverse([for(pt = fillet) [p - pt.x, pt.y] ]) // reflect for trailing edge
+    ) concat(fillet, [ [root_w / 2, -hw / 2], [p / 2 - crest_w / 2, ha], [p / 2 + crest_w / 2, ha], [p - root_w / 2, -hw / 2] ], reflection);
+
+module involute_rack_profile(m, z, w, pa = 20, clearance = undef) { //! Calculate rack profile given module, number of teeth and pressure angle
+    p = PI * m;                                     // Pitch
+    hf = 1.25 * m;                                  // Dedendum
+    tooth = involute_rack_tooth_profile(m, pa, clearance);
+    teeth = [for(i = [0 : z - 1], pt = tooth) [pt.x + i * p, pt.y] ];
+
+    polygon(concat([[0, -w], [0, -hf]], teeth, [[z * p, -hf ], [z * p, -w]])); // Add the corners
+}
+
+function involute_worm_profile(m, pa = 20, clearance = undef) = //! Calculate worm profile suitable for passing to thread()
+    let(tooth = involute_rack_tooth_profile(m),
+        pitch = PI * m,
+        y_min = min([for(p = tooth) p.y])
+    ) [for(p = tooth) [p.x - pitch / 2, p.y - y_min, 0]];   // Offset to be positive in y, centred in x and add 0 z ordintate
--- a/utils/hanging_hole.scad
+++ b/utils/hanging_hole.scad
@@ -39,11 +39,13 @@ module hanging_hole(z, ir, h = 100, h2 = 100) { //! Hole radius ```ir``` hanging
    infill_angle = z % (2 * layer_height) ? -45 : 45;
    below = min(z + eps, h2);
    big = 1000;
-
    render(convexity = 3) translate_z(z)
        union() {
            translate_z(2 * layer_height)
-                polyhole(ir - eps, h - 2 * layer_height);
+                if(sides(ir) > 4)
+                    polyhole(ir - eps, h - 2 * layer_height);
+                else
+                    poly_cylinder(ir, h - 2 * layer_height);

            difference() {
                translate_z(-below)
--- a/utils/horiholes.scad
+++ b/utils/horiholes.scad
@@ -0,0 +1,55 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+
+//
+//! Utilities for depicting the staircase slicing of horizontal holes made with [`teardrop_plus()`](#teardrops), see <https://hydraraptor.blogspot.com/2020/07/horiholes-2.html>
+//
+include <../utils/core/core.scad>
+
+function teardrop_plus_x(r, y, h) = //! Calculate the ordinate of a compensated teardrop given y and layer height.
+    let(fr = h / 2,
+        hpot = r + fr,
+        x2 = sqr(hpot) - sqr(y),
+        x = x2 > 0 ? sqrt(x2) : 0
+    )
+    max(0,
+        y < hpot / sqrt(2) ? x - fr :
+        y < hpot           ? hpot * sqrt(2) - y - fr :
+        0);
+
+module horihole(r, z, h = 0, center = true) { //! For making horizontal holes that don't need support material and are correct dimensions
+    bot_layer = floor((z - r) / layer_height);
+    top_layer = ceil((z + r) / layer_height);
+    render(convexity = 5)
+        extrude_if(h, center)
+            for(i = [bot_layer : top_layer]) {
+                Z = i * layer_height;
+                y = Z - z + layer_height / 2;
+                x = teardrop_plus_x(r, y, layer_height);
+                if(x > 0)
+                    translate([0, y])
+                        difference() {
+                            square([2 * x + layer_height, layer_height], center = true);
+
+                            for(end = [-1, 1])
+                                translate([end * (x + layer_height / 2), 0])
+                                    circle(d = layer_height, $fn = 32);
+                        }
+             }
+}
--- a/utils/layout.scad
+++ b/utils/layout.scad
@@ -28,6 +28,6 @@ function layout_offset(widths, i, gap = 2) = //! Calculate the offset for the ``

 module layout(widths, gap = 2, no_offset = false) //! Layout children passing ```$i```
    translate([no_offset ? -widths[0] / 2 : 0, 0])
-        for($i = [0 : len(widths) - 1])
+        for($i = [0 : 1 : len(widths) - 1])
            translate([layout_offset(widths, $i, gap), 0])
                children();
--- a/utils/maths.scad
+++ b/utils/maths.scad
@@ -20,7 +20,10 @@
 //
 //! Maths utilities for manipulating vectors and matrices.
 //
-function sqr(x) = x * x;
+function sqr(x) = x * x;                        //! Square x
+function radians(degrees) = degrees * PI / 180; //! Convert radians to degrees
+function degrees(radians) = radians * 180 / PI; //! Convert degrees to radians
+

 function translate(v) = let(u = is_list(v) ? len(v) == 2 ? [v.x, v.y, 0] //! Generate a 4x4 translation matrix, ```v``` can be ```[x, y]```, ```[x, y, z]``` or ```z```
                                                         : v
@@ -63,6 +66,12 @@ function rot3_z(a) = //! Generate a 3x3 matrix to rotate around z
          [ s,  c,  0],
          [ 0,  0,  1] ];

+function rot2_z(a) = //! Generate a 2x2 matrix to rotate around z
+    let(c = cos(a),
+        s = sin(a))
+        [ [ c, -s],
+          [ s,  c] ];
+
 function scale(v) = let(s = is_list(v) ? v : [v, v, v]) //!  Generate a 4x4 matrix that scales by ```v```, which can be a vector of xyz factors or a scalar to scale all axes equally
                        [
                          [s.x, 0,   0,   0],
@@ -90,3 +99,42 @@ function euler(R) = let(ay = asin(-R[2][0]), cy = cos(ay)) //! Convert a rotatio
    cy ? [ atan2(R[2][1] / cy, R[2][2] / cy), ay, atan2(R[1][0] / cy, R[0][0] / cy) ]
       : R[2][0] < 0 ? [atan2( R[0][1],  R[0][2]),  180, 0]
                     : [atan2(-R[0][1], -R[0][2]), -180, 0];
+
+module position_children(list, t) //! Position children if they are on the Z = 0 plane when transformed by t
+    for(p = list)
+        let(q = t * p)
+            if(abs(transform([0, 0, 0], q).z) < 0.01)
+                multmatrix(q)
+                    children();
+
+// Matrix inversion: https://www.mathsisfun.com/algebra/matrix-inverse-row-operations-gauss-jordan.html
+
+function augment(m) = let(l = len(m), n = identity(l)) [ //! Augment a matrix by adding an identity matrix to the right
+    for(i = [0 : l - 1])
+        concat(m[i], n[i])
+];
+
+function rowswap(m, i, j) = [ //! Swap two rows of a matrix
+    for(k = [0 : len(m) - 1])
+        k == i ? m[j] : k == j ? m[i] : m[k]
+];
+
+function solve_row(m, i) = let(diag = m[i][i]) [ //! Make diagonal one by dividing the row by it and subtract from other rows to make column zero
+    for(j = [0 : len(m) - 1])
+        i == j ? m[j] / diag : m[j] - m[i] * m[j][i] / diag
+];
+
+function nearly_zero(x) = abs(x) < 1e-5; //! True if x is close to zero
+
+function solve(m, i = 0, j = 0) = //! Solve each row ensuring diagonal is not zero
+    i < len(m) ?
+        assert(i + j < len(m), "matrix is singular")
+         solve(!nearly_zero(m[i + j][i]) ? solve_row(j ? rowswap(m, i, i + j) : m, i) : solve(m, i, j + 1), i + 1)
+        : m;
+
+function invert(m) = let(n =len(m), m = solve(augment(m))) [ //! Invert a matrix
+    for(i = [0 : n - 1]) [
+        for(j = [n : 2 * n - 1])
+             each m[i][j]
+    ]
+];
--- a/utils/quadrant.scad
+++ b/utils/quadrant.scad
@@ -23,18 +23,21 @@
 include <../utils/core/core.scad>

 module quadrant(w, r, center = false) { //! Draw a square with one rounded corner, can be centered on the arc centre, when ```center``` is ```true```.
-    offset = center ? r - w : 0;
-    translate([offset, offset])
+    h = is_list(w) ? w.y : w;
+    w = is_list(w) ? w.x : w;
+    offset_w = center ? r - w : 0;
+    offset_h = center ? r - h : 0;
+    translate([offset_w, offset_h])
        hull() {
            intersection() {
-                translate([w - r, w - r])
+                translate([w - r, h - r])
                    circle4n(r);

-                square(w);
+                square([w, h]);
            }

            square([w, eps]);

-            square([eps, w]);
+            square([eps, h]);
        }
 }
--- a/utils/thread.scad
+++ b/utils/thread.scad
@@ -26,6 +26,8 @@
 //! Threads are by default solid, so the male version is wrapped around a cylinder and the female inside a tube. This can be suppressed to just get the helix, for
 //! example to make a printed pot with a screw top lid.
 //!
+//! A left hand thread can be made by using mirror([0,1]).
+//!
 //! Threads with a typical 60 degree angle appear too bright with OpenSCAD's primitive lighting model as they face towards the lights more than the top and sides of
 //! a cylinder. To get around this a colour can be passed to thread that is used to colour the cylinder and then toned down to colour the helix.
 //!
@@ -47,7 +49,7 @@ function thread_profile(h, crest, angle, overlap = 0.1) = //! Create thread prof
    let(base = crest + 2 * (h + overlap) * tan(angle / 2))
        [[-base / 2, -overlap, 0], [-crest / 2, h, 0], [crest / 2, h, 0], [base / 2, -overlap, 0]];

-module thread(dia, pitch, length, profile, center = true, top = -1, bot = -1, starts = 1, solid = true, female = false, colour = undef) { //! Create male or femail thread, ends can be tapered, chamfered or square
+module thread(dia, pitch, length, profile, center = true, top = -1, bot = -1, starts = 1, solid = true, female = false, colour = undef) { //! Create male or female thread, ends can be tapered, chamfered or square
    //
    // Apply colour if defined
    //
@@ -61,10 +63,12 @@ module thread(dia, pitch, length, profile, center = true, top = -1, bot = -1, st
    // Extract some properties from the profile, perhaps they should be stored in it.
    //
    h = max([for(p = sprofile) p.y]);
-    maxx = max([for(p = sprofile) p.x]);
-    minx = min([for(p = sprofile) p.x]);
-    crest_xmax = max([for(p = sprofile) if(p.x != maxx) p.x]);
-    crest_xmin = min([for(p = sprofile) if(p.x != minx) p.x]);
+    xs = [for(p = sprofile) p.x];
+    maxx = max(xs);
+    minx = min(xs);
+    crest_xs = [for(p = sprofile) if(p.y == h) p.x];
+    crest_xmax = max(crest_xs);
+    crest_xmin = min(crest_xs);
    //
    // If the ends don't taper we need an extra half turn past the ends to be cropped horizontally.
    //
@@ -129,11 +133,13 @@ module thread(dia, pitch, length, profile, center = true, top = -1, bot = -1, st
                    render() intersection() {
                        polyhedron(points, ends_faces);

-                        len = length - 2 * eps;
+                        shorten = !is_undef(colour);
+                        len = shorten ? length - 2 * eps : length;
+                        offset = shorten ? eps : 0;
                        rotate_extrude()
                            if(female) {
                                difference() {
-                                    translate([0, eps])
+                                    translate([0, offset])
                                        square([r + h + overlap, len]);

                                    if(top_chamfer_h)
@@ -146,7 +152,7 @@ module thread(dia, pitch, length, profile, center = true, top = -1, bot = -1, st
                            else
                                difference() {
                                    hull() {
-                                        translate([0, eps])
+                                        translate([0, offset])
                                            square([r, len]);

                                        translate([0, bot_chamfer_h])
--- a/vitamins/axial.scad
+++ b/vitamins/axial.scad
@@ -24,6 +24,7 @@ include <../utils/core/core.scad>
 include <../utils/round.scad>

 module wire_link(d, l, h = 1, tail = 3) { //! Draw a wire jumper link.
+    vitamin(str("wire_link(", d, ", ", l, arg(h, 1, "h"), arg(tail, 3, "tail"),  "): Wire link ", d, "mm x ", l / inch(1), "\""));
    r = d;
    $fn = 32;

@@ -57,13 +58,16 @@ module orientate_axial(length, height, pitch, wire_d) { // Orient horizontal or
    min_pitch = ceil((length + 1) / inch(0.1)) * inch(0.1);
    lead_pitch = pitch ? pitch : min_pitch;
    if(lead_pitch >= min_pitch) {
-        wire_link(wire_d, lead_pitch, height);
+        not_on_bom()
+            wire_link(wire_d, lead_pitch, height);
+
        translate_z(height)
            rotate([0, 90, 0])
                children();
    }
    else {
-        wire_link(wire_d, lead_pitch, length + 0.7 + wire_d);
+        not_on_bom()
+            wire_link(wire_d, lead_pitch, length + 0.7 + wire_d);

        translate([-pitch / 2, 0, length / 2 + 0.2])
            children();
--- a/vitamins/ball_bearing.scad
+++ b/vitamins/ball_bearing.scad
@@ -52,21 +52,21 @@ module ball_bearing(type) { //! Draw a ball bearing
        rim_chamfer = rim / 6;
        rotate_extrude()
            hull() {
-                translate([or - rim / 2, 0])
-                    square([rim, h - 2 * rim_chamfer], center = true);
+                translate([or - rim, -h / 2 + rim_chamfer])
+                    square([rim, h - 2 * rim_chamfer]);

-                translate([or - rim / 2 - rim_chamfer, 0])
-                    square([rim - rim_chamfer, h], center = true);
+                translate([or - rim, -h / 2])
+                    square([rim - rim_chamfer, h]);
            }

        hub_chamfer = hub / 6;
        rotate_extrude()
            hull() {
-                translate([ir + hub / 2, 0])
-                    square([hub, h - 2 * hub_chamfer], center = true);
+                translate([ir, -h / 2 + hub_chamfer])
+                    square([hub, h - 2 * hub_chamfer]);

-                translate([ir + hub / 2 + hub_chamfer, 0])
-                    square([hub - hub_chamfer, h], center = true);
+                translate([ir + hub_chamfer, -h / 2])
+                    square([hub - hub_chamfer, h]);
            }
    }

--- a/vitamins/ball_bearings.scad
+++ b/vitamins/ball_bearings.scad
@@ -16,11 +16,12 @@
 // You should have received a copy of the GNU General Public License along with NopSCADlib.
 // If not, see <https://www.gnu.org/licenses/>.
 //
-BB624 =  ["624",  4,  13, 5, "blue",      1.2, 1.2];  // 624 ball bearing for idlers
-BB608 =  ["608",  8,  22, 7, "OrangeRed", 1.4, 2.0];  // 608 bearings for wades
-BB6200 = ["6200", 10, 30, 9, "black",     2.3, 3.6];  // 6200 bearings for KP pillow blocks
-BB6201 = ["6201", 12, 32, 10, "black",    2.4, 3.7];  // 6201 bearings for KP pillow blocks
-BB6808 = ["6808", 40, 52, 7, "black",     1.5, 1.6];
-ball_bearings = [BB624, BB608, BB6200, BB6201, BB6808];
+BBSMR95 =  ["SMR95", 5,  9,  2.5, "silver",    0.5, 0.7];  // SMR95 ball bearing for FlexDrive extruder
+BB624   =  ["624",   4,  13, 5,   "blue",      1.2, 1.2];  // 624 ball bearing for idlers
+BB608   =  ["608",   8,  22, 7,   "OrangeRed", 1.4, 2.0];  // 608 bearings for wades
+BB6200   = ["6200",  10, 30, 9,   "black",     2.3, 3.6];  // 6200 bearings for KP pillow blocks
+BB6201   = ["6201",  12, 32, 10,  "black",     2.4, 3.7];  // 6201 bearings for KP pillow blocks
+BB6808   = ["6808",  40, 52, 7,   "black",     1.5, 1.6];
+ball_bearings = [BBSMR95, BB624, BB608, BB6200, BB6201, BB6808];

 use <ball_bearing.scad>
--- a/vitamins/belt.scad
+++ b/vitamins/belt.scad
@@ -24,29 +24,31 @@
 //! To make the back of the belt run against a smooth pulley on the outside of the loop specify a negative pitch radius.
 //!
 //! By default the path is a closed loop but a gap length and position can be specified to make open loops.
+//! To draw the gap its XY position is specified by ```gap_pos```. ```gap_pos.z``` can be used to specify a rotation if the gap is not at the bottom of the loop.
 //!
 //! Individual teeth are not drawn, instead they are represented by a lighter colour.
 //
 include <../utils/core/core.scad>
 use <../utils/rounded_polygon.scad>
+use <../utils/maths.scad>

 function belt_pitch(type)        = type[1]; //! Pitch in mm
 function belt_width(type)        = type[2]; //! Width in mm
 function belt_thickness(type)    = type[3]; //! Total thickness including teeth
 function belt_tooth_height(type) = type[4]; //! Tooth height
-function belt_pitch_height(type) = belt_tooth_height(type) + type[4]; //! Offset of the pitch radius from the tips of the teeth
+function belt_pitch_height(type) = type[5] + belt_tooth_height(type); //! Offset of the pitch radius from the tips of the teeth

-function no_point(str) = chr([for(c = str) if(c == ".") ord("p") else ord(c)]);
+function belt_pitch_to_back(type) = belt_thickness(type) - belt_pitch_height(type); //! Offset of the back from the pitch radius
 //
 // We model the belt path at the pitch radius of the pulleys and the pitch line of the belt to get an accurate length.
 // The belt is then drawn by offseting each side from the pitch line.
 //
-module belt(type, points, gap = 0, gap_pt = undef, belt_colour = grey20, tooth_colour = grey50) { //! Draw a belt path given a set of points and pitch radii where the pulleys are. Closed loop unless a gap is specified
+module belt(type, points, gap = 0, gap_pos = undef, belt_colour = grey(20), tooth_colour = grey(50)) { //! Draw a belt path given a set of points and pitch radii where the pulleys are. Closed loop unless a gap is specified
    width = belt_width(type);
    pitch = belt_pitch(type);
    thickness = belt_thickness(type);
    part = str(type[0],pitch);
-    vitamin(str("belt(", no_point(part), "x", width, ", ", points, arg(gap, 0), arg(gap_pt, undef), "): Belt ", part," x ", width, "mm x ", length, "mm"));
+    vitamin(str("belt(", no_point(part), "x", width, ", ", points, arg(gap, 0), arg(gap_pos, undef), "): Belt ", part," x ", width, "mm x ", length, "mm"));

    len = len(points);

@@ -56,24 +58,28 @@ module belt(type, points, gap = 0, gap_pt = undef, belt_colour = grey20, tooth_c

    module shape() rounded_polygon(points, tangents);

+    ph = belt_pitch_height(type);
+    th = belt_tooth_height(type);
    module gap()
        if(gap)
-            translate(gap_pt)
-                square([gap, thickness + eps], center = true);
+            translate([gap_pos.x, gap_pos.y])
+                rotate(is_undef(gap_pos.z) ? 0 : gap_pos.z)
+                    translate([0, ph - thickness / 2])
+                        square([gap, thickness + eps], center = true);

    color(belt_colour)
        linear_extrude(width, center = true)
            difference() {
-                offset(thickness - belt_pitch_height(type)) shape();
-                offset(-belt_pitch_height(type) + belt_tooth_height(type)) shape();
+                offset(-ph + thickness ) shape();
+                offset(-ph + th) shape();
                gap();
-
            }
+
    color(tooth_colour)
        linear_extrude(width, center = true)
            difference() {
-                offset(-belt_pitch_height(type) + belt_tooth_height(type)) shape();
-                offset(-belt_pitch_height(type)) shape();
+                offset(-ph + th) shape();
+                offset(-ph) shape();
                gap();
            }
 }
--- a/vitamins/blower.scad
+++ b/vitamins/blower.scad
@@ -39,7 +39,7 @@ function blower_top(type)         = type[14]; //! Thickness of the top
 function blower_wall(type)        = type[15]; //! Side wall thickness
 function blower_lug(type)         = type[16]; //! Height of the lugs

-fan_colour = grey20;
+fan_colour = grey(20);

 module blower(type) { //! Draw specified blower
    length = blower_length(type);
--- a/vitamins/button.scad
+++ b/vitamins/button.scad
@@ -46,7 +46,7 @@ module square_button(type, colour = "yellow") { //! Draw square button with spec
    pitch = (w/ 2 - wall - rivit * 0.75);
    stem = square_button_cap_stem(type);

-    color(grey20) {
+    color(grey(20)) {
        rounded_rectangle([w, w, h - 0.5], r = wall, center = false);

        for(x = [-1, 1], y = [-1, 1])
--- a/vitamins/camera.scad
+++ b/vitamins/camera.scad
@@ -0,0 +1,89 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+
+//
+//! PCB cameras.
+//
+include <../utils/core/core.scad>
+use <pcb.scad>
+
+function camera_pcb(type)           = type[2]; //! The PCB part of the camera
+function camera_lens_offset(type)   = type[3]; //! Offset of the lens center from the PCB centre
+function camera_lens(type)          = type[4]; //! Stack of lens parts, can be round, rectanular or rounded rectangular, with optional tapered aperture
+function camera_connector_pos(type) = type[5]; //! The flex connector block for the camera itself's position
+function camera_connector_size(type)= type[6]; //! The flex connector block for the camera itself's size
+
+module camera_lens(type, offset = 0) //! Draw the lens stack, with optional offset for making a clearance hole
+    color(grey(20))
+        translate(camera_lens_offset(type))
+            for(p = camera_lens(type)) {
+                size = p[0];
+                r = p[1] + offset;
+                app = p[2];
+                if(size.x)
+                    rounded_rectangle(size + [2 * offset, 2 * offset, round_to_layer(offset)], r, center = false);
+                else
+                    translate_z(size.y)
+                        rotate_extrude()
+                            difference() {
+                                square([r, size.z + round_to_layer(offset)]);
+
+                                if(app)
+                                    translate([0, size.z])
+                                        hull() {
+                                            translate([0, -eps])
+                                                square([app.y, eps * 2]);
+
+                                            translate([0, -app.z])
+                                                square([app.x, app.z]);
+                                        }
+                            }
+            }
+
+module camera(type) {           //! Draw specified PCB camera
+    vitamin(str("camera(", type[0], "): ", type[1]));
+    pcb = camera_pcb(type);
+
+    not_on_bom()
+        pcb(pcb);
+
+    translate_z(pcb_thickness(pcb)) {
+        camera_lens(type);
+
+        conn = camera_connector_size(type);
+        if(conn) {
+            pos = camera_connector_pos(type);
+            color(grey(20))
+                translate(pos)
+                    rounded_rectangle(conn, 0.5, center = false);
+
+            flex = [5, 0.1];
+            color("orange")
+                hull() {
+                    translate_z(flex.y /2)
+                        translate(camera_lens_offset(type) + [0, camera_lens(type)[0][0].y / 2])
+                            cube([flex.x, eps, flex.y], center = true);
+
+                    translate_z(conn.z - flex.y)
+                        translate([camera_lens_offset(type).x, pos.y] - [0, conn.y / 2])
+                             cube([flex.x, eps, flex.y], center = true);
+                }
+        }
+    }
+}
--- a/vitamins/cameras.scad
+++ b/vitamins/cameras.scad
@@ -0,0 +1,73 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+include <smds.scad>
+
+rpi_camera_v1_pcb = ["", "",  25, 24, 1, 0, 2.1, 0, "green", false, [[2, -2], [-2, -2], [2, 9.6], [-2, 9.6]],
+    [
+        [12,   3.25,  0, "-flat_flex", true],
+        [-4.5, -5,    0, "smd_led", LED0603, "red"],
+        [-5.5, -4,    0, "smd_res", RES0603, "1K2"],
+    ],
+    []];
+
+rpi_camera_v1 = ["rpi_camera_v1", "Raspberry Pi camera V1", rpi_camera_v1_pcb, [0, 9.6 - 12],
+    [
+        [[8, 8, 3], 0],
+        [[0, 0, 4], 7.5 / 2],
+        [[0, 0, 5], 5.5 / 2, [1.5/2, 2/2, 0.5]],
+    ],
+    [0, 12 - 1.5 - 2.5], [8, 5, 1]
+];
+
+rpi_camera_v2_pcb = ["", "",  25, 23.862, 1, 2, 2.2, 0, "green", false, [[2, -2], [-2, -2], [2, -14.5], [-2, -14.5]],
+    [
+        [12.5,   2.75,  0, "-flat_flex", true],
+    ],
+    []];
+
+rpi_camera_v2 = ["rpi_camera_v2", "Raspberry Pi camera V2", rpi_camera_v2_pcb, [0, 9.6 - 12],
+    [
+        [[8.5, 8.5, 3], 0],
+        [[0, 0, 4], 7.5 / 2],
+        [[0, 0, 5], 5.5 / 2, [1.5/2, 2/2, 0.5]],
+    ],
+    [-13.8 + 12.5, 23.862 / 2 - 4.7], [8.5, 4, 1]
+];
+
+rpi_camera_pcb = ["", "",  36, 36, 1.6, 0, 3.2, 0, "green", false, [[3.5, -3.5], [-3.5, -3.5], [3.5, 3.5], [-3.5, 3.5]],
+    [
+        [18,    4.25,  0, "-flat_flex", true],
+        [-3.8, -7.8,  0, "smd_led", LED0805, "red"],
+    ],
+    []];
+
+rpi_camera = ["rpi_camera", "Raspberry Pi focusable camera", rpi_camera_pcb, [0, 0],
+    [
+        [[13, 13, 3], 0],
+        [[22,  4, 3], 2 - eps],
+        [[0, 0, 8.5], 7],
+        [[0, 0,  12], 6],
+        [[0, 11, 4.3], 14 / 2, [8/2, 11/2, 1]],
+    ],
+    [0, 18 - 1.5 - 2.5], [8, 5, 1.6]
+];
+
+cameras = [rpi_camera_v1, rpi_camera, rpi_camera_v2];
+
+use <camera.scad>
--- a/vitamins/circlip.scad
+++ b/vitamins/circlip.scad
@@ -33,7 +33,7 @@ function circlip_a(type)         = type[5];     //! Size of the lugs
 function circlip_b(type)         = type[6];     //! Widest part of the taper
 function circlip_d5(type)        = type[7];     //! Plier hole diameter

-circlip_colour = grey20;
+circlip_colour = grey(20);
 closed_angle = 25;

 module internal_circlip(type, open = 0) { //! Draw specified internal circlip, open = 0, for nominal size installed, 1 for relaxed uninstalled, -1 for squeezed to install
--- a/vitamins/d_connector.scad
+++ b/vitamins/d_connector.scad
@@ -23,9 +23,9 @@
 include <../utils/core/core.scad>
 use <../utils/thread.scad>

-d_pillar_colour                   = grey90;
-d_plug_shell_colour               = grey80;
-d_plug_insulator_colour           = grey20;
+d_pillar_colour                   = grey(90);
+d_plug_shell_colour               = grey(80);
+d_plug_insulator_colour           = grey(20);

 function  d_flange_length(type)    = type[1];   //! Length of the flange
 function  d_lengths(type)          = type[2];   //! Lengths of the D for plug and socket
--- a/vitamins/dip.scad
+++ b/vitamins/dip.scad
@@ -91,7 +91,7 @@ module dil_socket(rows, w, pitch = inch(0.1)) {
    hole = [0.8, 0.5];
    pin_l = 3;

-    color(grey20) {
+    color(grey(20)) {
        linear_extrude(h)
            difference() {
                square([width, length], center = true);
@@ -129,7 +129,7 @@ module dip(n, part, size, w, pitch, pin) { //! Draw DIP package
    D = [3, 0.6];

    translate_z(pdip_pin_s(pin)) {
-        color(grey20) {
+        color(grey(20)) {
            rotate([90, 0, 0])
                linear_extrude(size.x, center = true)
                    difference() {
--- a/vitamins/extrusion.scad
+++ b/vitamins/extrusion.scad
@@ -122,7 +122,7 @@ module extrusion(type, length, center = true, cornerHole = false) { //! Draw the

    vitamin(str("extrusion(", type[0], ", ", length, arg(cornerHole, false, "cornerHole"), "): Extrusion ", type[0], " x ", length, "mm"));

-    color(grey90)
+    color(grey(90))
        linear_extrude(length, center = center)
            extrusion_cross_section(type, cornerHole);
 }
--- a/vitamins/fan.scad
+++ b/vitamins/fan.scad
@@ -28,7 +28,7 @@ use <nut.scad>
 use <washer.scad>
 use <../utils/tube.scad>

-fan_colour = grey20;
+fan_colour = grey(20);

 function fan_width(type)          = type[0];    //! Width of square
 function fan_depth(type)          = type[1];    //! Depth of fan
--- a/vitamins/fans.scad
+++ b/vitamins/fans.scad
@@ -17,28 +17,28 @@
 // If not, see <https://www.gnu.org/licenses/>.
 //

-//          w   d   b   h      s              h     t    o   b  b    a
-//          i   e   o   o      c              u     h    u   l  o    p
-//          d   p   r   l      r              b     i    t   a  s    p
-//          t   t   e   e      e                    c    e   d  s    e
-//          h   h              w              d     k    r   e       r
-//                      p                     i     n        s  d    t
-//                      i                     a     e    d           u
-//                      t                           s    i           r
-//                      c                           s    a           e
-//                      h
+//          w     d   b   h      s              h     t    o   b  b    a
+//          i     e   o   o      c              u     h    u   l  o    p
+//          d     p   r   l      r              b     i    t   a  s    p
+//          t     t   e   e      e                    c    e   d  s    e
+//          h     h              w              d     k    r   e       r
+//                        p                     i     n        s  d    t
+//                        i                     a     e    d           u
+//                        t                           s    i           r
+//                        c                           s    a           e
+//                        h
 //
-fan120x25= [120,25, 116,52.5,  M4_dome_screw, 41,   4,  140, 9, 0,   137];
-fan80x38 = [80, 38, 75, 35.75, M4_dome_screw, 40,   4.3, 84, 7, 0,   85];
-fan80x25 = [80, 25, 75, 35.75, M4_dome_screw, 40,   4.3, 84, 7, 0,   85];
-fan70x15 = [70, 15, 66, 30.75, M4_dome_screw, 29,   3.8, 70 ,7, 0,   undef];
-fan60x25 = [60, 25, 57, 25,    M4_dome_screw, 31.5, 3.6, 64, 7, 0,   63];
-fan60x15 = [60, 15, 57, 25,    M4_dome_screw, 29,   2.4, 60, 7, 7.7, 63];
-fan50x15 = [50, 15, 48, 20,    M4_dome_screw, 25,   12.5,100,7, 0,   undef];
-fan40x11 = [40, 11, 37, 16,    M3_dome_screw, 25,   7.5,100, 9, 0,   undef];
-fan30x10 = [30, 10, 27, 12,    M3_dome_screw, 17,   10, 100, 5, 0,   undef];
-fan25x10 = [25, 10, 24, 10,   M2p5_pan_screw, 16,   10, 100, 5, 0,   undef];
-fan17x8  = [17,  8, 16, 6.75,  M2_cap_screw,  12.6,  8, 100, 7, 0,   undef];
+fan120x25= [120, 25, 116,52.5,  M4_dome_screw, 41,   4,  140, 9, 0,   137];
+fan80x38 = [80,  38, 75, 35.75, M4_dome_screw, 40,   4.3, 84, 7, 0,   85];
+fan80x25 = [80,  25, 75, 35.75, M4_dome_screw, 40,   4.3, 84, 7, 0,   85];
+fan70x15 = [70,  15, 66, 30.75, M4_dome_screw, 29,   3.8, 70 ,7, 0,   undef];
+fan60x25 = [60,  25, 57, 25,    M4_dome_screw, 31.5, 3.6, 64, 7, 0,   63];
+fan60x15 = [60,  15, 57, 25,    M4_dome_screw, 29,   2.4, 60, 7, 7.7, 63];
+fan50x15 = [50,  15, 48, 20,    M4_dome_screw, 25,  12.5,100, 7, 0,   undef];
+fan40x11 = [40,  11, 37, 16,    M3_dome_screw, 25,   7.5,100, 9, 0,   undef];
+fan30x10 = [30,  10, 27, 12,    M3_dome_screw, 17,   10, 100, 5, 0,   undef];
+fan25x10 = [25.4,10, 24, 10,   M2p5_pan_screw, 16,   10, 100, 5, 0,   undef];
+fan17x8  = [17,   8, 16, 6.75,  M2_cap_screw,  12.6,  8, 100, 7, 0,   undef];

 fans = [fan17x8, fan25x10, fan30x10, fan40x11, fan50x15, fan60x15, fan60x25, fan70x15, fan80x25, fan80x38, fan120x25];

--- a/vitamins/fuseholder.scad
+++ b/vitamins/fuseholder.scad
@@ -61,7 +61,7 @@ module fuseholder(thickness) { //! Fuseholder with nut in place for specified pa
    //
    // Nut
    //
-    colour = grey40;
+    colour = grey(40);
    vflip()
        translate_z(thickness)
            explode(height) {
--- a/vitamins/hot_ends.scad
+++ b/vitamins/hot_ends.scad
@@ -33,8 +33,7 @@
 //                                                                                       h      t     s   t              t     t
 //                                                                                              h
 //
-JHeadMk4  = ["JHeadMk4",  jhead, "JHead MK4",           64,  5.1, 16,    50, grey20,     12,    4.64, 14, [0, 2.94, -5], 20,   20];
-JHeadMk5  = ["JHeadMk5",  jhead, "JHead MK5",         51.2,  5.1, 16,    40, grey20,     12,    4.64, 13, [0, 2.38, -5], 20,   20];
+JHeadMk5  = ["JHeadMk5",  jhead, "JHead MK5",         51.2,  4.75,16,    40, grey(20),   12,    4.64, 13, [0, 2.38, -5], 20,   20];
 E3Dv5     = ["E3Dv5",     e3d,   "E3D V5 direct",       70,  3.7, 16,  50.1, "silver",   12,    6,    15, [1, 5,  -4.5], 14.5, 28];
 E3Dv6     = ["E3Dv6",     e3d,   "E3D V6 direct",       62,  3.7, 16,  42.7, "silver",   12,    6,    15, [1, 5,  -4.5], 14,   21];
 E3D_clone = ["E3D_clone", e3d,   "E3D clone aliexpress",66,  6.8, 16,    46, "silver",   12,    5.6,  15, [1, 5,  -4.5], 14.5, 21];
--- a/vitamins/hygrometer.scad
+++ b/vitamins/hygrometer.scad
@@ -51,7 +51,7 @@ module hygrometer() { //! Draw a hygrometer
    vitamin("hygrometer(): Mini LCD Digital Thermometer / Hygrometer");

    explode(40) {
-        color(grey30)
+        color(grey(30))
            rotate_extrude()
                polygon([
                    [0, 0],
--- a/vitamins/iec.scad
+++ b/vitamins/iec.scad
@@ -134,7 +134,7 @@ module iec(type) { //! Draw specified IEC connector
        }
    }

-    color(grey20) {
+    color(grey(20)) {
        // Flange
        flange_t = iec_flange_t(type);
        linear_extrude(flange_t)
--- a/vitamins/insert.scad
+++ b/vitamins/insert.scad
@@ -24,17 +24,26 @@ include <../utils/core/core.scad>
 use <../utils/quadrant.scad>
 use <../utils/thread.scad>

-function insert_length(type)         = type[1]; //! Length
-function insert_outer_d(type)        = type[2]; //! Outer diameter at the top
+function insert_length(type)         = type[1];     //! Length
+function insert_outer_d(type)        = type[2];     //! Outer diameter at the top
 function insert_hole_radius(type)    = type[3] / 2; //! Radius of the required hole in the plastic
-function insert_screw_diameter(type) = type[4]; //! Screw size
-function insert_barrel_d(type)       = type[5]; //! Diameter of the main barrel
-function insert_ring1_h(type)        = type[6]; //! Height of the top and middle rings
-function insert_ring2_d(type)        = type[7]; //! Diameter of the middle ring
-function insert_ring3_d(type)        = type[8]; //! Diameter of the bottom ring
+function insert_screw_diameter(type) = type[4];     //! Screw size
+function insert_barrel_d(type)       = type[5];     //! Diameter of the main barrel
+function insert_ring1_h(type)        = type[6];     //! Height of the top and middle rings
+function insert_ring2_d(type)        = type[7];     //! Diameter of the middle ring
+function insert_ring3_d(type)        = type[8];     //! Diameter of the bottom ring

 function insert_hole_length(type) = round_to_layer(insert_length(type));

+function insert_nose_length(type, d) = let( //! The length before the second ring.
+        length = insert_length(type),
+        ring1_h = insert_ring1_h(type),
+        chamfer1 = (insert_ring2_d(type) - insert_barrel_d(type)) / 2,
+        chamfer2 = (insert_ring3_d(type) - insert_barrel_d(type)) / 2,
+        ring2_h = ring1_h + chamfer1,
+        gap = (length - ring1_h - ring2_h - chamfer2) / 3
+    ) ring1_h + gap + ring2_h - d + insert_barrel_d(type);
+
 module insert(type) { //! Draw specified insert
    length = insert_length(type);
    ring1_h = insert_ring1_h(type);
@@ -42,12 +51,12 @@ module insert(type) { //! Draw specified insert
    chamfer1 = (insert_ring2_d(type) - insert_barrel_d(type)) / 2;
    chamfer2 = (insert_ring3_d(type) - insert_barrel_d(type)) / 2;
    ring2_h = ring1_h + chamfer1;
-    gap = (length - ring1_h - ring2_h- chamfer2) / 3;
+    gap = (length - ring1_h - ring2_h - chamfer2) / 3;

    vitamin(str("insert(", type[0], "): Heatfit insert M", insert_screw_diameter(type)));
    $fn = 64;
    thread_d = insert_screw_diameter(type);
-    explode(20, offset =[0, 0, -5]) translate_z(eps) vflip() {
+    explode(20, offset = [0, 0, -5]) translate_z(eps) vflip() {
        r1 = thread_d / 2;
        r2 = insert_barrel_d(type) / 2;
        r3 = insert_ring3_d(type) / 2;
@@ -58,7 +67,7 @@ module insert(type) { //! Draw specified insert
        h3 = ring1_h + gap + ring2_h;
        h4 = ring1_h + gap + ring2_h + gap;
        color(brass)
-            rotate_extrude()
+            rotate_extrude(convexity = 3)
                polygon([
                    [r1, 0],
                    [r1, length],
--- a/vitamins/inserts.scad
+++ b/vitamins/inserts.scad
@@ -29,7 +29,7 @@
 //                          d         d          h    d    d
 //                                         d
 //
-F1BM2   = [ "F1BM",    4.0, 3.6, 3.2, 2,   3.0,  1.0, 3.4, 3.1 ];
+F1BM2   = [ "F1BM2",    4.0, 3.6, 3.2, 2,   3.0,  1.0, 3.4, 3.1 ];
 F1BM2p5 = [ "F1BM2p5", 5.8, 4.6, 4.0, 2.5, 3.65, 1.6, 4.4, 3.9 ];
 F1BM3   = [ "F1BM3",   5.8, 4.6, 4.0, 3,   3.65, 1.6, 4.4, 3.9 ];
 F1BM4   = [ "F1BM4",   8.2, 6.3, 5.6, 4,   5.15, 2.3, 6.0, 5.55 ];
--- a/vitamins/jhead.scad
+++ b/vitamins/jhead.scad
@@ -29,7 +29,6 @@ include <zipties.scad>
 use <wire.scad>
 use <../utils/tube.scad>

-MK4_heater = [ 12.76, 15.88, 8.22, (15.88 / 2 - 4.5), (12.76 / 2 - 0.5 - 2.5 / 2),  (-15.88 / 2 + 5), 9.5, 3];
 MK5_heater = [ 12.76, 12.76, 8.22, (12.76 / 2 - 3.75), (12.76 / 2 - 0.5 - 2.5 / 2), (-12.76 / 2 + 4), 8,   2];

 function heater_width(type)  = type[0];
@@ -71,7 +70,7 @@ module heater_block(type, resistor, thermistor) {
        cone_start_r = nozzle_cone(type) / 2;
        straight = 1;
        nozzle_r = 0.4 / 2;
-        translate_z(-h / 2) vflip()
+        translate([nozzle_x(type), 0, -h / 2]) vflip()
            rotate_extrude()
                polygon([
                    [nozzle_r,     0],
@@ -86,7 +85,7 @@ module heater_block(type, resistor, thermistor) {
 module jhead_hot_end(type, filament) {
    resistor = RIE1212UB5C5R6;
    thermistor = Epcos;
-    heater = type == JHeadMk4 ? MK4_heater : MK5_heater;
+    heater = MK5_heater;

    insulator_length = hot_end_insulator_length(type);
    inset = hot_end_inset(type);
@@ -106,7 +105,7 @@ module jhead_hot_end(type, filament) {

                    square([hot_end_insulator_diameter(type) / 2 - chamfer, insulator_length]);
                }
-                square([3.2 / 2, insulator_length]);
+                square([(filament + 0.2) / 2, insulator_length]);

                translate([hot_end_groove_dia(type) / 2, insulator_length - hot_end_inset(type) - hot_end_groove(type)])
                    square([100, hot_end_groove(type)]);
@@ -122,7 +121,7 @@ module jhead_hot_end(type, filament) {
 module jhead_hot_end_assembly(type, filament, naked = false) { //! Assembly with resistor, thermistor, tape, sleaving and ziptie
    resistor = RIE1212UB5C5R6;
    thermistor = Epcos;
-    heater = type == JHeadMk4 ? MK4_heater : MK5_heater;
+    heater = MK5_heater;

    insulator_length = hot_end_insulator_length(type);
    inset = hot_end_inset(type);
@@ -139,7 +138,7 @@ module jhead_hot_end_assembly(type, filament, naked = false) { //! Assembly with
    //
    // silcone tape
    //
-    if(!naked)
+    if(is_undef(naked) || !naked)
        color("red")
            if(exploded())
                translate([0, max(hot_end_insulator_diameter(type) / 2, heater_length(heater) / 2 - nozzle_x(heater)),
@@ -157,7 +156,7 @@ module jhead_hot_end_assembly(type, filament, naked = false) { //! Assembly with
    //
    // Zip tie and heatshrink
    //
-    if(!naked)
+    if(!naked  && !is_undef(naked))
        rotate(10) {
            dia =  hot_end_insulator_diameter(type);
            scale([1, (bundle + dia) / dia])
--- a/vitamins/kp_pillow_block.scad
+++ b/vitamins/kp_pillow_block.scad
@@ -25,7 +25,7 @@ use <../utils/tube.scad>
 use <washer.scad>
 use <ball_bearing.scad>

-kp_pillow_block_colour = grey70;
+kp_pillow_block_colour = grey(70);

 function kp_diameter(type)        = type[1]; //! Rod hole diameter
 function kp_hole_offset(type)     = type[2]; //! Rod hole offset
--- a/vitamins/led_meter.scad
+++ b/vitamins/led_meter.scad
@@ -85,7 +85,8 @@ module meter(type, colour = "red", value = "888", display_colour = false) //! Dr
        translate([0, meter_shunt_y(type), size.z])
            vflip()
                color("#b87333")
-                    wire_link(shunt.y, shunt.x, shunt.z, tail = 2);
+                    not_on_bom()
+                        wire_link(shunt.y, shunt.x, shunt.z, tail = 2);
 }

 clearance = 0.1;
--- a/vitamins/light_strip.scad
+++ b/vitamins/light_strip.scad
@@ -137,7 +137,6 @@ module light_strip(type, segs = undef) { //! Draw specified light strip, segs ca
            linear_extrude(0.55 + eps)
                resistor_positions()
                    square([2.1, 1.5 + 2 * eps], center = true);
-
    }

    if(show_rays)
@@ -148,8 +147,9 @@ wall = 1.8;
 clearance = 0.2;
 function light_strip_clip_slot(light) = light_strip_width(light) + clearance;       //! Clip slot size
 function light_strip_clip_depth(light) = 10;                                        //! Depth of the clip
-function light_strip_clip_length(light) = light_strip_clip_slot(light) + 2 * wall;  //! Outside length
-function light_strip_clip_width(light) = light_strip_depth(light) + 2 * wall;       //! Outside width
+function light_strip_clip_length(light) = light_strip_clip_slot(light) + 2 * wall;  //! Outside length of clip
+function light_strip_clip_width(light) = light_strip_depth(light) + 2 * wall;       //! Outside width of clip
+function light_strip_clip_wall() = wall;                                            //! Clip wall thickness

 module light_strip_clip(light) { //! Make a clip to go over the strip to be incorporated into a bracket
    linear_extrude(light_strip_clip_depth(light), convexity = 2)
--- a/vitamins/light_strips.scad
+++ b/vitamins/light_strips.scad
@@ -26,7 +26,7 @@
 //                                                                                         e     s    c
 //                                                                                               s    k
 Rigid5050 = ["Rigid5050", "rigid SMD5050 low profile",              500, 36, 3, 14.4,   7, 10.4, 0.9, 1.2];
-RIGID5050 = ["RIGID5050", "rigid SMD5050"            ,              500, 36, 3, 14.4, 8.6, 10.4, 0.9, 1.6];
+RIGID5050 = ["RIGID5050", "rigid SMD5050"            ,              500, 36, 3, 14.4, 8.6,  9.8, 0.8, 1.6];

 light_strips = [Rigid5050,  RIGID5050,];

--- a/vitamins/linear_bearing.scad
+++ b/vitamins/linear_bearing.scad
@@ -24,9 +24,9 @@ include <../utils/core/core.scad>

 use <../utils/tube.scad>

-bearing_colour = grey70;
-groove_colour = grey60;
-seal_colour = grey30;
+bearing_colour = grey(70);
+groove_colour = grey(60);
+seal_colour = grey(30);


 function bearing_length(type)           = type[1];   //! Total length
--- a/vitamins/magnet.scad
+++ b/vitamins/magnet.scad
@@ -0,0 +1,49 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+
+//
+//! Cylindrical and ring magnets.
+//
+include <../utils/core/core.scad>
+
+function magnet_od(type)    = type[1]; //! Outer diameter
+function magnet_id(type)    = type[2]; //! Inside diameter if a ring
+function magnet_h(type)     = type[3]; //! Height
+function magnet_r(type)     = type[4]; //! Corner radius
+
+module magnet(type) { //! Draw specified magnet
+    od = magnet_od(type);
+    id = magnet_id(type);
+    h = magnet_h(type);
+    r = magnet_r(type);
+
+    //vitamin(str("magnet(", type[0], "): Magnet ", od, "mm diameter, ", h, "mm high", id ? str(", ", id, "mm bore") : "" ));
+
+    or = od / 2;
+    ir = id / 2;
+    color(silver)
+        rotate_extrude()
+            union() {
+                translate([ir, 0])
+                    rounded_square([or - ir, h], r, center = false);
+                if(!ir)
+                    square([r, h]);
+            }
+
+}
--- a/vitamins/magnets.scad
+++ b/vitamins/magnets.scad
@@ -0,0 +1,30 @@
+//
+// NopSCADlib Copyright Chris Palmer 2020
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+//
+//! Cylindrical and ring magnets.
+//
+
+//                          od,        id,        h,         r
+MAG8x4x4p2 = ["MAG8x4x4p2", 8,         4.2,       4,         0.5];
+MAG484     = ["MAG484",     inch(1/4), inch(1/8), inch(1/4), 0.5];
+MAG5x8     = ["MAG484",     8,         0,         5,         0.5];
+
+magnets = [MAG8x4x4p2, MAG484, MAG5x8];
+
+use <magnet.scad>
--- a/vitamins/microswitches.scad
+++ b/vitamins/microswitches.scad
@@ -24,8 +24,8 @@ small_leg  = [0.9,  3.3, 0.4, 0];
 medium_leg = [0.5,  3.9, 3.2, 1.6, [0, -0.5]];
 large_leg  = [11.4, 0.8, 6.3, 1.8, [1.7, 0]];

-small_microswitch  = ["small_microswitch", "DM1-00P-110-3",      5.8, 6.5,  12.8, 0, 2,    [[-3.25, -1.65], [3.25, -1.65]], 2.9, 1.2, [-1.95, 3.75], [[-5.08, -4.95], [0,    -4.9],  [5.08, -4.9]  ], small_leg,  grey20, "white"  ];
-medium_microswitch = ["medium_microswitch","SS-01 or SS-5GL",    6.4, 10.2, 19.8, 1, 2.35, [[-4.8,  -2.6 ], [4.7,  -2.6 ]], 3.2, 2,   [-2.8,  5.8 ], [[-8.05, -7.05], [0.75, -7.05], [8.05, -7.05] ], medium_leg, grey20, "burlywood" ];
+small_microswitch  = ["small_microswitch", "DM1-00P-110-3",      5.8, 6.5,  12.8, 0, 2,    [[-3.25, -1.65], [3.25, -1.65]], 2.9, 1.2, [-1.95, 3.75], [[-5.08, -4.95], [0,    -4.9],  [5.08, -4.9]  ], small_leg,  grey(20), "white"  ];
+medium_microswitch = ["medium_microswitch","SS-01 or SS-5GL",    6.4, 10.2, 19.8, 1, 2.35, [[-4.8,  -2.6 ], [4.7,  -2.6 ]], 3.2, 2,   [-2.8,  5.8 ], [[-8.05, -7.05], [0.75, -7.05], [8.05, -7.05] ], medium_leg, grey(20), "burlywood" ];
 large_microswitch  = ["large_microswitch", "Saia G3 low force", 10.4, 15.9, 28.0, 2, 3.1,  [[-11.1, -5.15], [11.2,  5.15]], 4,   2.75,[-9.1,  9.55], [[19.7,   2.19], [19.7, -3.45],  [8.3, -10.45] ], large_leg,  "ivory", "white" ];

 microswitches = [small_microswitch, medium_microswitch, large_microswitch];
--- a/vitamins/module.scad
+++ b/vitamins/module.scad
@@ -87,7 +87,7 @@ module mod(type) {  //! Draw specified module
                linear_extrude(body_l, center = true)
                    profile();

-        color(grey20)
+        color(grey(20))
            for(end = [-1, 1])
                translate([end * body_l / 2, 0, 0])
                    rotate([90, 0, end * 90])
--- a/vitamins/nut.scad
+++ b/vitamins/nut.scad
@@ -55,7 +55,7 @@ module nut(type, nyloc = false, brass = false, nylon = false) { //! Draw specifi
    vitamin(str("nut(", type[0], arg(nyloc, false, "nyloc"), arg(brass, false, "brass"), arg(nylon, false, "nylon"),
                   "): Nut M", nut_size(type), " x ", thickness, "mm ", desc));

-    colour = brass ? brass_colour : nylon ? grey30: grey70;
+    colour = brass ? brass_colour : nylon ? grey(30): grey(70);
    explode(nyloc ? 10 : 0) {
        color(colour) {
            linear_extrude(thickness)
@@ -147,7 +147,7 @@ module sliding_t_nut(type) {
    tabSizeZ = nut_thickness(type);
    holeRadius  = nut_size(type) / 2;

-    color(grey80)
+    color(grey(80))
        extrusionSlidingNut(size, tabSizeY1, tabSizeY2, tabSizeZ, holeRadius, 0, hammerNut);
 }

@@ -204,7 +204,7 @@ module nut_square(type, brass = false, nylon = false) { //! Draw specified squar
    vitamin(str("nut(", type[0], arg(brass, false, "brass"), arg(nylon, false, "nylon"),
                   "): Nut M", nut_size(type), "nS ", width, " x ", thickness, "mm ", desc));

-    colour = brass ? brass_colour : nylon ? grey30 : grey70;
+    colour = brass ? brass_colour : nylon ? grey(30) : grey(70);
    color(colour)
        difference() {
            linear_extrude(thickness) {
--- a/vitamins/opengrab.scad
+++ b/vitamins/opengrab.scad
@@ -25,7 +25,7 @@
 include <../utils/core/core.scad>
 use <../utils/thread.scad>

-pitch = 33.8;
+pitch = 33.8 / 2;
 width = 40;
 depth = 18;
 magnet = 4.3;
@@ -37,10 +37,16 @@ pole_l = 36;
 poles = 15;

 module opengrab_hole_positions()    //! Position children at the screw positions
-    for(x = [-1, 1], y = [-1, 1])
-        translate([x * pitch / 2, y * pitch / 2, 0])
-            children();
+    let($d = 3.2)
+        for($x = [-pitch, pitch], $y = [-pitch, pitch])
+            translate([$x, $y])
+                children();

+module opengrab_side_hole_positions() //! Position children at the two 4mm hole
+    let($d = 4, pitch = width / 2 - 3.5)
+        for($x = [-pitch, pitch])
+            translate([$x, 0])
+                children();

 function opengrab_width() = width;              //! Module width
 function opengrab_depth() = depth;              //! Module height
@@ -53,7 +59,7 @@ module opengrab() { //! Draw OpenGrab module
        translate_z(magnet / 2 + eps)
            cube([width, width, magnet - eps], center = true);

-    color(grey80) {
+    color(grey(80)) {
        gap = (width - poles * pole_w + 3 * eps) / (poles - 1);
        pitch = pole_w + gap;
        for(i = [0 : poles - 1])
@@ -82,18 +88,17 @@ module opengrab() { //! Draw OpenGrab module
 }

 module opengrab_target() { //! Draw OpenGrab target
-    vitamin("opengrab_target(): OpenGrab  silicon steel target plate");
+    vitamin("opengrab_target(): OpenGrab silicon steel target plate");

-     color(grey80)
+     color(grey(80))
        linear_extrude(target)
            difference() {
                square([width, width], center = true);

                opengrab_hole_positions()
-                    circle(d = 3.2);
+                    circle(d = $d);

-                for(side = [-1, 1])
-                    translate([side * (width / 2 - 3.5), 0])
-                        circle(d = 4);
+                opengrab_side_hole_positions()
+                    circle(d = $d);
        }
 }
--- a/vitamins/panel_meter.scad
+++ b/vitamins/panel_meter.scad
@@ -87,7 +87,7 @@ module panel_meter(type) { //! Draw panel mounted LCD meter module
        translate([x * (bezel.x / 2 - bevel), y * (bezel.y / 2 - bevel)])
            rounded_cylinder(r = r, r2 = bevel, h = bezel.z);

-    color(grey30) union() {
+    color(grey(30)) union() {
        //
        // Bezel and aperture
        //
--- a/vitamins/panel_meters.scad
+++ b/vitamins/panel_meters.scad
@@ -25,8 +25,8 @@
 PZEM021   = ["PZEM021", "Peacefair PZEM-021 AC digital multi-function meter", [84.6, 44.7, 24.4], [89.6, 49.6, 2.3], 1.5, [1, 1], [51, 30, 5], [1.3, 10, 6], 15.5, 0];
 PZEM001   = ["PZEM001", "Peacefair PZEM-001 AC digital multi-function meter", [62  , 52.5, 24.4], [67,   57.5, 2.0], 2.0, [1, 1], [61, 46,-3], [1.2, 10, 6], 15.5, 0,
             [36, 36, 1.9], [0, 0], false, 0, 0, [
-                [[25,  8, 0], [0, 0, 2], 4, grey90],
-                [[25, -8, 0], [0, 0, 2], 4, grey90],
+                [[25,  8, 0], [0, 0, 2], 4, grey(90)],
+                [[25, -8, 0], [0, 0, 2], 4, grey(90)],

            ]];

--- a/vitamins/pcb.scad
+++ b/vitamins/pcb.scad
@@ -53,6 +53,8 @@ function pcb_accessories(type)  = type[12]; //! List of accessories to go on the
 function pcb_grid(type)         = type[13]; //! Grid if a perfboard
 function pcb_polygon(type)      = type[14]; //! Optional outline polygon for odd shaped boards
 function pcb_screw(type, cap = hs_cap) = Len(type[15]) ? type[15] : find_screw(cap, screw_smaller_than(pcb_hole_d(type))); //! Mounting screw type
+function pcb_size(type) = [pcb_length(type), pcb_width(type), pcb_thickness(type)]; //! Length, width and thickness in a vector
+

 function pcb_grid_pos(type, x, y, z = 0) = //! Returns a pcb grid position
    [-pcb_length(type) / 2 + pcb_grid(type).x + 2.54 * x,
@@ -248,7 +250,7 @@ module rj45(cutout = false) { //! Draw RJ45 Ethernet connector
                        cube([h, w, eps], center = true);
                }

-                color(grey30) {
+                color(grey(30)) {
                    linear_extrude(l - 0.2, center = true)
                        difference() {
                            square([h - 0.1, w - 0.1], center = true);
@@ -279,7 +281,7 @@ module jack(cutout = false) { //! Draw 3.5mm jack
            rotate([0, 90, 0])
                cylinder(d = d + 2 * panel_clearance, h = 100);
        else
-            color(grey20)
+            color(grey(20))
                rotate([0, 90, 0]) {
                    linear_extrude(l / 2)
                        difference() {
@@ -331,8 +333,9 @@ function hdmi_height2(type)   = type[6]; //! Inside height in the middle
 function hdmi_height(type)    = type[7]; //! Outside height above the PCB
 function hdmi_thickness(type) = type[8]; //! Wall thickness of the metal

-hdmi_full = [ "hdmi_full", "HDMI socket",      12,  14,   10,  3,    4.5, 6.5, 0.5 ];
-hdmi_mini = [ "hdmi_mini", "Mini HDMI socket", 7.5, 10.5, 8.3, 1.28, 2.5, 3.2, 0.35 ];
+hdmi_full = [ "hdmi_full", "HDMI socket",        12,   14,   10,  3,    4.5, 6.5, 0.5 ];
+hdmi_mini = [ "hdmi_mini", "Mini HDMI socket",    7.5, 10.5, 8.3, 1.28, 2.5, 3.2, 0.35 ];
+hdmi_micro = [ "hdmi_micro", "Micro HDMI socket", 8.5,  5.9, 4.43, 1.4, 2.3, 3,   0.3 ];

 module hdmi(type, cutout = false) { //! Draw HDMI socket
    vitamin(str("hdmi(", type[0], "): ", type[1]));
@@ -435,6 +438,39 @@ module usb_uA(cutout = false) { //! Draw USB micro A connector
        }
 }

+module usb_C(cutout = false) { //! Draw USB C connector
+    l = 7.35;
+    w = 8.94;
+    h = 3.26;
+    t = 0.4;
+    flange_h = 3;
+    flange_w = 8;
+
+    module O()
+        translate([0, h / 2])
+            rounded_square([w, h], h / 2 - 0.5, center = true);
+
+    if(cutout)
+        rotate([90, 0, 90])
+            linear_extrude(100)
+                offset(2 * panel_clearance)
+                    O();
+    else
+        color("silver") rotate([90, 0, 90]) {
+            linear_extrude(l, center = true)
+                difference() {
+                    O();
+
+                    offset(-t)
+                        O();
+                }
+
+            translate_z(-l / 2)
+                linear_extrude(2.51)
+                    O();
+
+        }
+}
 module usb_B(cutout = false) {  //! Draw USB B connector
    l = 16.4;
    w = 12.2;
@@ -508,7 +544,7 @@ module barrel_jack(cutout = false) { //! Draw barrel power jack
    if(cutout)
        ;
    else {
-        color(grey20) rotate([0, 90, 0]) {
+        color(grey(20)) rotate([0, 90, 0]) {
            linear_extrude(l, center = true) {
                difference() {
                    translate([-h / 2, 0])
@@ -580,7 +616,7 @@ module uSD(size, cutout = false) { //! Draw uSD socket
                        cube([size.x, size.z, t], center = true);
                }
            if(w > 0)
-                color(grey20)
+                color(grey(20))
                    rotate([90, 0, 90])
                        translate_z(t)
                            linear_extrude(size.y - t, center = true)
@@ -608,7 +644,7 @@ module flex(cutout = false) { //! Draw flexistrip connector
    if(cutout)
        ;
    else {
-        color(grey30) {
+        color(grey(30)) {
            translate_z(0.5)
                cube([l, w, 1], center = true);

@@ -636,56 +672,52 @@ module flex(cutout = false) { //! Draw flexistrip connector

                        translate([0, -w / 2 + slot_offset + slot_w / 2])
                            square([slot_l, slot_w], center = true);
-
                    }
        }
    }
 }

-module flat_flex(cutout = false) { //! Draw flat flexistrip connector as used on RPI0
-    l1 = 17;
-    w1 = 1.4;
-    h1 = 1.2;
+small_ff = [[11.8, 0.9], [17, 1.4, 1.2], [12, 1.6, 1.2], [16, 1.1, 1.2]];
+large_ff = [[16,  1.25], [22, 1.5, 2.5], [16, 4.0, 2.5], [21, 0,   2.5]];

-    l2 = 15.4;
-    w2 = 1.6;
-    h2 = 1.0;
+function ff_slot(type)  = type[0]; //! Flat flex slot size
+function ff_latch(type) = type[1]; //! Flat flex latch size
+function ff_mid(type)   = type[2]; //! Flat flex middle section size
+function ff_back(type)  = type[3]; //! Flat flex back section size

-    l3 = 16;
-    w3 = 1.1;
-    h3 = 1.2;
+module flat_flex(type, cutout = false) { //! Draw flat flexistrip connector as used on RPI0
+    slot = ff_slot(type);
+    latch = ff_latch(type);
+    mid =   ff_mid(type);
+    back =  ff_back(type);

-    l4 = 12;
-
-    slot_l = 11.8;
-    slot_h = 0.9;
-
-    w = w1 + w2 + w3;
+    w = latch.y + mid.y + back.y;
    if(cutout)
        ;
    else {
-        color(grey30) {
-            translate([w / 2 - w1, 0, h1 / 2])
-                rotate([90, 0, 90])
-                    linear_extrude(w1)
+        color(grey(30))
+            translate([0, w / 2 - latch.y])
+                rotate([90, 0, 180])
+                    linear_extrude(latch.y)
                        difference() {
-                            square([l1, h1], center = true);
+                            translate([-latch.x / 2, 0])
+                                square([latch.x, latch.z]);

-                            translate([0, -h1 / 2])
-                                square([slot_l, slot_h * 2], center = true);
+                            square([slot.x, slot.y * 2], center = true);
                        }

-        }
-        color(grey90) {
-            translate([-w / 2 + w3 / 2, 0, h3 / 2])
-                cube([w3, l3, h3], center = true);
+        color("ivory") {
+            translate([-back.x / 2, -w / 2])
+                if(back.y)
+                    cube(back);

-            translate([-w / 2 + w3 + w2 / 2, 0, h2 / 2])
-                cube([w2, l2, h2], center = true);
-
-             translate([-w / 2 + w3 + w2 / 2, 0, h3 / 2])
-                cube([w2, l4, h3], center = true);
+            translate([-mid.x / 2,  -w / 2 + back.y])
+                cube(mid);
       }
+
+       color(grey(80))
+            translate([-back.x / 2, -w / 2 + back.y + eps])
+                cube([back.x, mid.y - 2 * eps, mid.z - eps]);
    }
 }

@@ -883,21 +915,23 @@ module pcb_component(comp, cutouts = false, angle = undef) { //! Draw pcb compon
    function param(n, default = 0) = len(comp) > n ? comp[n] : default;
    rotate(comp.z) {
        // Components that have a cutout parameter go in this section
-        if(show(comp, "2p54header"))    pin_header(2p54header, comp[4], comp[5], param(6, false), false, cutouts, colour = param(7, undef));
+        if(show(comp, "2p54header"))    pin_header(2p54header, comp[4], comp[5], param(6, false), param(8, false), cutouts, colour = param(7, undef));
        if(show(comp, "2p54boxhdr"))    box_header(2p54header, comp[4], comp[5], param(6, false), cutouts);
        if(show(comp, "2p54socket"))    pin_socket(2p54header, comp[4], comp[5], param(6, false), param(7, 0), param(8, false), cutouts, param(9, undef));
-        if(show(comp, "chip"))          chip(comp[4], comp[5], comp[6], param(7, grey30), cutouts);
+        if(show(comp, "chip"))          chip(comp[4], comp[5], comp[6], param(7, grey(30)), cutouts);
        if(show(comp, "rj45"))          rj45(cutouts);
        if(show(comp, "usb_A"))         usb_Ax1(cutouts);
        if(show(comp, "usb_Ax2"))       usb_Ax2(cutouts);
        if(show(comp, "usb_uA"))        usb_uA(cutouts);
        if(show(comp, "usb_B"))         usb_B(cutouts);
+        if(show(comp, "usb_C"))         usb_C(cutouts);
        if(show(comp, "jack"))          jack(cutouts);
        if(show(comp, "barrel_jack"))   barrel_jack(cutouts);
        if(show(comp, "hdmi"))          hdmi(hdmi_full, cutouts);
        if(show(comp, "mini_hdmi"))     hdmi(hdmi_mini, cutouts);
+        if(show(comp, "micro_hdmi"))    hdmi(hdmi_micro, cutouts);
        if(show(comp, "flex"))          flex(cutouts);
-        if(show(comp, "flat_flex"))     flat_flex(cutouts);
+        if(show(comp, "flat_flex"))     flat_flex(param(4, false) ? large_ff : small_ff, cutouts);
        if(show(comp, "uSD"))           uSD(comp[4], cutouts);
        if(show(comp, "trimpot10"))     trimpot10(param(4, false), cutouts);
        if(show(comp, "molex_usb_Ax2")) molex_usb_Ax2(cutouts);
@@ -919,11 +953,13 @@ module pcb_component(comp, cutouts = false, angle = undef) { //! Draw pcb compon
            if(show(comp, "led"))           led(comp[4], comp[5], 2.6);
            if(show(comp, "pdip"))          pdip(comp[4], comp[5], param(6, false), param(7, inch(0.3)));
            if(show(comp, "ax_res"))        ax_res(comp[4], comp[5], param(6, 5), param(7, 0));
+            if(show(comp, "link"))          wire_link(l = comp[4], h = param(5, 1), d = param(6, 0.8), tail = param(7, 3));
            if(show(comp, "D_plug"))        translate_z(d_pcb_offset(comp[4])) d_plug(comp[4], pcb = true);
            if(show(comp, "molex_hdr"))     molex_254(comp[4]);
            if(show(comp, "jst_xh"))        jst_xh_header(jst_xh_header, comp[4], param(5, false), param(6, "white"), param(7, undef));
            if(show(comp, "potentiometer")) potentiometer(param(4, 5), param(5, 9));
-            if(show(comp, "buzzer"))        buzzer(param(4, 9), param(5, 12), param(6, grey20));
+            if(show(comp, "buzzer"))        buzzer(param(4, 9), param(5, 12), param(6, grey(20)));
+            if(show(comp, "smd_res"))       smd_resistor(comp[4], comp[5]);
        }
    }
 }
--- a/vitamins/pcbs.scad
+++ b/vitamins/pcbs.scad
@@ -112,7 +112,7 @@ DuetE = ["DuetE", "Duet 2 Ethernet electronics",
                                                                     [109.8, -58.8,   0, "chip", inch(0.03), inch(0.06), 1, "red"],             // Bed heater

                                                                     [ 2.3,  -37.2,   0, "chip", 3.6, 4.8, 2.0, "silver"],  // Reset switch
-                                                                     [ 0.0,  -37.2,   0, "chip", 2.0, 2.6, 1.4, grey20],    // Reset button
+                                                                     [ 0.0,  -37.2,   0, "chip", 2.0, 2.6, 1.4, grey(20)],    // Reset button
                                                                    ],
                                                                    [": Micro SD card", ": Cat 5 patch cable 300mm"]];

@@ -217,6 +217,25 @@ RPI3 =  ["RPI3", "Raspberry Pi 3",     85,    56,    1.4, 3,    2.75, 6, "green"
    [": Micro SD card"],
    [32.5 - 9.5 * 2.54, 52.5 - 1.27, 20, 2]];

+RPI4 = ["RPI4", "Raspberry Pi 4", 85, 56, 1.4, 3, 2.75, 6, "green", false, [[3.5, 3.5], [61.5, 3.5], [61.5, -3.5], [3.5, -3.5]], [
+    [32.5, -3.5, 0, "2p54header", 20, 2],
+    [-6.5, 9, 0, "usb_Ax2"],
+    [-6.5, 27, 0, "usb_Ax2"],
+    [-8.5, 45.75, 0, "rj45"],
+
+    [ 4, 28, 90, "flex"],
+    [11.2, 3.675 - 1.6, -90, "usb_C"],
+    [ 26,  2.5, -90, "micro_hdmi"],
+    [39.5, 2.5, -90, "micro_hdmi"],
+    [46.5, 11.5, -90, "flex"],
+    [ 54, 6, -90, "jack"],
+
+    [ 29.25, 32.5, 0, "chip", 14, 14, 2.4],
+    [ 60, -22.3, 0, "chip", 9, 9, 0.6],
+    [7.75, 28, 180, "-uSD", [12, 11.5, 1.28]]
+    ], [": Micro SD card"], [32.5 - 9.5 * 2.54, 52.5 - 1.27, 20, 2]
+];
+
 RPI0 =  ["RPI0", "Raspberry Pi Zero",     65,    30,    1.4, 3,    2.75, 6, "green", false, [[3.5, 3.5], [-3.5, 3.5], [-3.5, -3.5], [3.5, -3.5]],
    [//[32.5, -3.5,   0, "2p54header", 20, 2],
     [25.5,  13,      0, "chip",       12, 12, 1.2],
@@ -224,7 +243,7 @@ RPI0 =  ["RPI0", "Raspberry Pi Zero",     65,    30,    1.4, 3,    2.75, 6, "gre
     [54,    2,     -90, "usb_uA"],
     [41.4,  2,     -90, "usb_uA"],
     [7.25,  16.7,  180, "uSD", [12, 11.5, 1.4]],
-     [-1.3,    15,    0, "flat_flex"],
+     [-1.3,    15,  -90, "flat_flex"],
    ],
    [": Micro SD card"],
    [32.5 - 9.5 * 2.54, 26.5 - 1.27, 20, 2]];
@@ -391,7 +410,7 @@ RAMPSEndstop = ["RAMPSEndstop", "RAMPS Endstop Switch",
    []];


-pcbs = [TP4056, MT3608, RAMPSEndstop, ExtruderPCB, PI_IO, ZC_A0591, RPI0, EnviroPlus, ArduinoUno3, ArduinoLeonardo, Keyes5p1, PSU12V1A, WD2002SJ, RPI3, DuetE, Duex2, Duex5, Melzi];
+pcbs = [TP4056, MT3608, RAMPSEndstop, ExtruderPCB, PI_IO, ZC_A0591, RPI0, EnviroPlus, ArduinoUno3, ArduinoLeonardo, Keyes5p1, PSU12V1A, WD2002SJ, RPI3, RPI4, DuetE, Duex2, Duex5, Melzi];

 perfboards = [PERF74x51, PERF70x50, PERF60x40, PERF70x30, PERF80x20];

--- a/vitamins/pillars.scad
+++ b/vitamins/pillars.scad
@@ -34,8 +34,8 @@ M3x13_hex_pillar       = ["M3x13_hex_pillar",       "hex",       3, 13, 5/cos(30
 M3x20_hex_pillar       = ["M3x20_hex_pillar",       "hex",       3, 20, 5/cos(30), 5/cos(30),  6, 6, "silver",  silver,  -8, 8];
 M3x20_nylon_pillar     = ["M3x20_nylon_pillar",     "nylon",     3, 20, 8,         5/cos(30),  0, 6, "white",   brass,   -6, 6];
 M4x17_nylon_pillar     = ["M4x17_nylon_pillar",     "nylon",     4, 20, 8,         5/cos(30),  0, 6, "white",   brass,   -6, 6];
-M3x20_nylon_hex_pillar = ["M3x20_nylon_hex_pillar", "hex nylon", 3, 20, 8/cos(30), 8/cos(30),  6, 6,  grey20,   grey20,  -6, 6];
-M3x10_nylon_hex_pillar = ["M3x10_nylon_hex_pillar", "hex nylon", 3, 10,5.5/cos(30),5.5/cos(30),6, 6,  grey20,   grey20,  -6, 6];
+M3x20_nylon_hex_pillar = ["M3x20_nylon_hex_pillar", "hex nylon", 3, 20, 8/cos(30), 8/cos(30),  6, 6,  grey(20),   grey(20),  -6, 6];
+M3x10_nylon_hex_pillar = ["M3x10_nylon_hex_pillar", "hex nylon", 3, 10,5.5/cos(30),5.5/cos(30),6, 6,  grey(20),   grey(20),  -6, 6];


 pillars = [M2x16_brass_pillar, M3x13_hex_pillar, M3x20_hex_pillar, M3x20_nylon_pillar, M4x17_nylon_pillar, M3x10_nylon_hex_pillar, M3x20_nylon_hex_pillar];
--- a/vitamins/pin_header.scad
+++ b/vitamins/pin_header.scad
@@ -58,18 +58,20 @@ module pin_header(type, cols = 1, rows = 1, smt = false, right_angle = false, cu

        translate_z(smt ? 3.5 - h : 0) {
            for(x = [0 : cols - 1], y = [0 : rows - 1]) {
-                translate([pitch * (x - (cols - 1) / 2), pitch * (y - (rows - 1) / 2), 0])
+                // Vertical part of the pin
+                translate([pitch * (x - (cols - 1) / 2), pitch * (y - (rows - 1) / 2)])
                    if(right_angle)
-                        pin(type, hdr_pin_below(type) + width / 2 + (y - 0.5) * pitch);
+                        pin(type, hdr_pin_below(type) + (y + 0.5) * pitch);
                    else
                        pin(type);

                if(right_angle) {
                    w = hdr_pin_width(type);
+                    // Horizontal part of the pin
                    rotate([-90, 0, 180])
-                        translate([pitch * (x - (cols - 1) / 2), -pitch * (y - (rows - 1) / 2) -width / 2, hdr_pin_below(type) - (y - 0.5) * pitch])
+                        translate([pitch * (x - (cols - 1) / 2), -pitch * (y - (rows - 1) / 2) - width / 2, hdr_pin_below(type) - (y - (rows - 1) / 2) * pitch])
                            pin(type, hdr_pin_length(type) - hdr_pin_below(type) + ra_offset + pitch / 2 + (y - 0.5) * pitch);
-
+                    // corner
                    translate([pitch * (x - (cols - 1) / 2), pitch * (y - (rows - 1) / 2) - w / 2, pitch * (y - (rows - 1) / 2) + width / 2 - w / 2])
                        rotate([0, -90, 0])
                            color(hdr_pin_colour(type))
@@ -78,7 +80,8 @@ module pin_header(type, cols = 1, rows = 1, smt = false, right_angle = false, cu
                                        square(w);
                }
            }
-            translate([0, right_angle ? -ra_offset - pitch / 2 : 0, right_angle ? width / 2 : 0])
+            // Insulator
+            translate([0, right_angle ? -ra_offset - (rows - 1) * pitch / 2 : 0, right_angle ? width / 2 : 0])
                rotate([right_angle ? 90 : 0, 0, 0])
                    color(base_colour)
                        linear_extrude(h)
@@ -176,7 +179,7 @@ module pin_socket(type, cols = 1, rows = 1, right_angle = false, height = 0, smt
        vitamin(str("pin_socket(", type[0], ", ", cols, ", ", rows, arg(right_angle, false, "right_angle"), arg(height, 0, "height"), arg(smt, false, "smt"),
                               "): Pin socket ", cols, " x ", rows, right_angle ? " right_angle" : ""));
        color(base_colour)
-            translate([0, right_angle ? -ra_offset - pitch / 2 : 0, right_angle ? width / 2 : 0])
+            translate([0, right_angle ? -ra_offset - (rows - 1) * pitch / 2 : 0, right_angle ? width / 2 : 0])
                rotate([right_angle ? 90 : 0, 0, 0])
                    translate_z(depth / 2)
                        linear_extrude(depth, center = true)
@@ -192,11 +195,11 @@ module pin_socket(type, cols = 1, rows = 1, right_angle = false, height = 0, smt
            for(x = [0 : cols - 1], y = [0 : rows -1]) {
                if(!smt)
                    translate([pitch * (x - (cols - 1) / 2), pitch * (y - (rows - 1) / 2), 0])
-                        pin(type, hdr_pin_below(type) + width / 2 + (y - 0.5) * pitch);
+                        pin(type, hdr_pin_below(type) + (y + 0.5) * pitch);

                if(right_angle) {
-                    rotate([-90, 0, 0])
-                        translate([pitch * (x - (cols - 1) / 2), -pitch * (y - (rows - 1) / 2) -width / 2, 0])
+                    rotate([-90, 0, 180])
+                        translate([pitch * (x - (cols - 1) / 2), -pitch * (y - (rows - 1) / 2) - width / 2, hdr_pin_below(type) - (y - (rows - 1) / 2) * pitch])
                            pin(type, hdr_pin_below(type) + (y - 0.5) * pitch);

                    w = hdr_pin_width(type);
@@ -210,7 +213,7 @@ module pin_socket(type, cols = 1, rows = 1, right_angle = false, height = 0, smt
    }
 }

-module jst_xh_header(type, pin_count, right_angle=false, colour, pin_colour) { //! Draw JST XH connector
+module jst_xh_header(type, pin_count, right_angle = false, colour = false, pin_colour = false) { //! Draw JST XH connector
    colour = colour ? colour : hdr_base_colour(type);
    pin_colour = pin_colour ? pin_colour : hdr_pin_colour(type);
    sizeY = 5.75;
--- a/vitamins/pin_headers.scad
+++ b/vitamins/pin_headers.scad
@@ -17,15 +17,15 @@
 // If not, see <https://www.gnu.org/licenses/>.
 //

-//                          p     p     b    p     p       b      Socket depth
-//                          i     i     e    i     i       a
-//                          t     n     l    n     n       s
-//                          c           o                  e
-//                          h     l     w    w     c
-//                                                         c
+//                               p     p     b    p     p       b         Socket depth
+//                               i     i     e    i     i       a
+//                               t     n     l    n     n       s
+//                               c           o                  e
+//                               h     l     w    w     c
+//                                                              c
 //
-2p54header = ["2p54header", 2.54, 11.6, 3.2, 0.66, "gold", grey20, 8.5];
-jst_xh_header = ["JST XH header",2.5,10,3.4, 0.64, "gold", grey90, 7];
+2p54header    = ["2p54header",   2.54, 11.6, 3.2, 0.66, "gold", grey(20), 8.5];
+jst_xh_header = ["JST XH header",2.5,  10,   3.4, 0.64, "gold", grey(90), 7];

 pin_headers = [ 2p54header ];

--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Chris Palmer	c99ed98a64	Can now have right angle pin headers on PCBs. Fixed bugs right angle pin headers with rows not equal to two. Added more tests for pin headers.	2020-09-11 00:20:28 +01:00
Chris Palmer	7f65e5d539	Added M2 dome head screws.	2020-09-10 18:38:24 +01:00
Chris Palmer	ffb7f87cc5	Fixed typo in insert name.	2020-09-10 18:27:56 +01:00
Chris Palmer	d0513c7299	Bodge to jhead to allow the ziptie and sleaving to be removed by setting naked to undef.	2020-09-06 12:33:44 +01:00
Chris Palmer	d1429a3b7d	Verboard can now have components on the underside, same as PCBs.	2020-09-06 12:32:42 +01:00
Chris Palmer	70513993bd	Can now put wire links on PCBs	2020-09-06 12:31:41 +01:00
Chris Palmer	9eb35accfd	Updated fan_guard picture.	2020-09-06 11:59:32 +01:00
Chris Palmer	7276f18566	Spacing	2020-09-06 11:56:55 +01:00
Chris Palmer	d944198dc4	25mm fans are actually 25.4, i.e. 1".	2020-09-06 11:55:58 +01:00
Chris Palmer	04f2499a9e	Moved no_point(str) from belt.scad to global.scad	2020-09-06 11:51:33 +01:00
Chris Palmer	1eb8b378e9	Added magnets	2020-08-23 16:46:29 +01:00
Chris Palmer	362dbdb4fc	Opengrab hole position children now passed diameter.	2020-08-22 14:32:23 +01:00
Chris Palmer	57d223d84b	Added insert_nose_length()	2020-08-22 14:31:06 +01:00
Chris Palmer	699385342f	quadrant can now have different height and width if passed a vector.	2020-08-22 14:27:01 +01:00
Chris Palmer	547a418cea	Hanging hole now works when the hole has only four sides.	2020-08-22 13:52:25 +01:00
Chris Palmer	b6d25048bc	Fixed belt gap positioning and added ability to rotae it.	2020-08-22 11:16:56 +01:00
Chris Palmer	4cdab218d9	Fix belt positioning bug. Belt gap position is now relative to the pitch line. Added belt_pitch_to_back().	2020-08-22 09:45:13 +01:00
Chris Palmer	b6147e5684	Code formatting	2020-08-13 17:02:14 +01:00
Chris Palmer	966ba536ed	Fixed J-Head nozzle offset. Reduced J-Head inset. Removed J-Head MK4.	2020-08-13 12:44:17 +01:00
Chris Palmer	2419d50641	Added more PTFE tube sizes and amde them whiter.	2020-08-13 12:30:39 +01:00
Chris Palmer	02211c2034	Added tubing_or() and center option.	2020-08-13 11:56:53 +01:00
Chris Palmer	77d73b075d	Added opengrab_side_hole_positions()	2020-08-13 11:55:31 +01:00
Chris Palmer	cb54a3131b	Added USB-C connector, micro hdmi and RPI4.	2020-08-01 19:38:22 +01:00
Chris Palmer	3cf275579c	Fixed ball bearing chamfers.	2020-07-31 01:33:33 +01:00
Chris Palmer	fb41f218fe	Added involute_gear_od() function.	2020-07-28 21:24:01 +01:00
Chris Palmer	e6a26bc7b1	Changed some teardrop holes to teardrop plus.	2020-07-20 20:39:01 +01:00
Chris Palmer	cb4fa40643	Reimplemented teardrop_plus() again.	2020-07-20 16:55:55 +01:00
Chris Palmer	6a26903514	Added blog links for horiholes.	2020-07-18 23:53:15 +01:00
Chris Palmer	d08d949887	Corrected teardrop_plus() shape to be an accurate compensation for slicer staircasing and added a plus option to tearslot(), etc. Added horiholes.scad to depict staircase holes.	2020-07-18 19:28:26 +01:00
Chris Palmer	574a73e527	More spelling	2020-07-14 23:39:36 +01:00
Chris Palmer	87a35126de	Spelling.	2020-07-14 09:48:30 +01:00
Chris Palmer	1ca485b66b	Added involute_worm_profile() and involute_rack_tooth_profile() functions.	2020-07-14 09:47:45 +01:00
Chris Palmer	bc919529d3	Tweaks to thread. Better thread crest detection. No longer shrtens thread by eps (to avoid z fight) if all one colour. Comment about left hand threads.	2020-07-14 09:42:32 +01:00
Chris Palmer	9f4ed2b915	Fixed capitalisation of Swiss_clips.scad.	2020-07-12 00:27:26 +01:00
Chris Palmer	7ce055373a	Add rack to mesh with involute spur gears.	2020-07-07 22:36:34 +01:00
Chris Palmer	71ac571346	Added a utility for making involute spur gears	2020-07-06 23:22:11 +01:00
Chris Palmer	e4d93366fa	Added degrees, radians and rot2_z() to maths.scad.	2020-07-06 12:43:24 +01:00
Chris Palmer	f047ac27f7	Added SMR95 ball bearing	2020-07-04 17:30:26 +01:00
Chris Palmer	a9e479d971	Documented camera lens module.	2020-07-04 14:57:01 +01:00
Chris Palmer	47b01af1ea	Added RPI camera V2 Add cameras to lib.scad	2020-07-04 14:54:19 +01:00
Chris Palmer	fe19eba237	Tweaked flat_flex connectors.	2020-07-04 14:14:25 +01:00
Chris Palmer	235f7b86e3	Camera connector position and size separated. Camera_lens() module added.	2020-07-04 09:55:38 +01:00
Chris Palmer	92d7e18b16	Added pcb_size() function.	2020-07-04 09:53:09 +01:00
Chris Palmer	6a7226120f	Fixed RPI camera component positions.	2020-06-30 18:57:14 +01:00
Chris Palmer	8aa00cd041	Added MGN12H rail and included MGN12 in the test.	2020-06-30 09:28:32 +01:00
Chris Palmer	f6b512da1f	Added a couple of Raspberry Pi cameras.	2020-06-29 23:03:54 +01:00
Chris Palmer	c7ea0939b9	Made flat_flex parametric and changed default orientation.	2020-06-29 23:01:34 +01:00
Chris Palmer	265b5ab555	Fixed layout to work with an empty list.	2020-06-27 20:00:47 +01:00
Chris Palmer	186dbbfd08	Added SMT resistors and 0603 LED.	2020-06-27 19:59:49 +01:00
Chris Palmer	60659a43f8	Added light_strip_clip_wall().	2020-06-24 16:42:17 +01:00
Chris Palmer	f412cb1736	Tweaked lightstrip dimensions.	2020-06-21 20:35:13 +01:00
Chris Palmer	2b878556fc	Bug fix to platters.scad for last change.	2020-06-21 16:00:26 +01:00
Chris Palmer	1f1a360b7c	Mods to allow panels and platters to be target specific or not.	2020-06-21 12:53:14 +01:00
Chris Palmer	a547c98995	Added shelf bracket to printed/box.scad.	2020-06-20 15:12:09 +01:00
Chris Palmer	d9fa8c8668	Added position children used for drilling holes on sheets.	2020-06-20 15:04:03 +01:00
Chris Palmer	bf5b6d7c30	Added matrix inversion	2020-06-20 15:01:01 +01:00
Chris Palmer	9cfde7f524	Updated readme for grey() change.	2020-06-20 14:56:38 +01:00
Chris Palmer	184f19ef04	Replaced grey constants with a function grey(). Done to reduced the number of global constants.	2020-06-20 10:17:29 +01:00