Merge branch 'martinbudden-rounded_right_triangle'

Fixed rounding error in hangin_hole assert.

core.scad

@@ -18,7 +18,7 @@
 //
 
 //
-// Include this file to use the miniumum library plus screws, nuts and washers
+// Include this file to use the minimum library plus screws, nuts and washers
 //
 include <utils/core/core.scad>
 //

global_defs.scad

@@ -33,10 +33,10 @@ $exploded       = is_undef($explode)         ? 0      : $explode;         // 1 f
 layer_height    = is_undef($layer_height)    ? 0.25   : $layer_height;    // layer heigth when printing
 extrusion_width = is_undef($extrusion_width) ? 0.5    : $extrusion_width; // filament width when printing
 nozzle          = is_undef($nozzle)          ? 0.45   : $nozzle;          // 3D printer nozzle
-cnc_bit_r       = is_undef($cnc_bit_r)       ? 1.2    : $cnc_bit_r;       // miniumum tool radius when milling 2D objects
+cnc_bit_r       = is_undef($cnc_bit_r)       ? 1.2    : $cnc_bit_r;       // minimum tool radius when milling 2D objects
 pp1_colour      = is_undef($pp1_colour)      ? [0, 146/255, 0] : $pp1_colour; // printed part colour 1, RepRap logo colour
-pp2_colour      = is_undef($pp2_colour)      ? "red"  : $pp2_colour;      // printed part colour 2
-pp3_colour      = is_undef($pp3_colour)      ? "blue" : $pp3_colour;      // printed part colour 3
+pp2_colour      = is_undef($pp2_colour)      ? "Crimson"  : $pp2_colour;  // printed part colour 2
+pp3_colour      = is_undef($pp3_colour)      ? "SteelBlue" : $pp3_colour; // printed part colour 3
 pp4_colour      = is_undef($pp4_colour)      ? "darkorange" : $pp4_colour;// printed part colour 4
 show_rays       = is_undef($show_rays)       ? false  : $show_rays;       // show camera sight lines and light direction
 show_threads    = is_undef($show_threads)    ? false  : $show_threads;    // show screw threads

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>
@@ -52,6 +54,7 @@ include <vitamins/ring_terminals.scad>
 include <vitamins/rails.scad>
 include <vitamins/rod.scad>
 include <vitamins/scs_bearing_blocks.scad>
+include <vitamins/shaft_couplings.scad>
 include <vitamins/sheets.scad>
 include <vitamins/sk_brackets.scad>
 include <vitamins/spools.scad>
@@ -83,9 +86,11 @@ 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>
+use <utils/rounded_right_triangle.scad>
 use <utils/layout.scad>
 use <utils/round.scad>
 use <utils/offset.scad>

libtest.scad

@@ -17,6 +17,23 @@
 // If not, see <https://www.gnu.org/licenses/>.
 //
 
+//!# NopSCADlib
+//! An ever expanding library of parts modelled in OpenSCAD useful for 3D printers and enclosures for electronics, etc.
+//!
+//! It contains lots of vitamins (the RepRap term for non-printed parts), some general purpose printed parts and some utilities.
+//! There are also Python scripts to generate Bills of Materials (BOMs),
+//! STL files for all the printed parts, DXF files for CNC routed parts in a project and a manual containing assembly
+//! instructions and exploded views by scraping markdown embedded in OpenSCAD comments, [see scripts](scripts/readme.md).
+//!
+//! A simple example project can be found [here](examples/MainsBreakOutBox/readme.md).
+//!
+//! For more examples of what it can make see the [gallery](gallery/readme.md).
+//!
+//! The license is GNU General Public License v3.0, see [COPYING](COPYING).
+//!
+//! See [usage](docs/usage.md) for requirements, installation instructions and a usage guide.
+//!
+//! <img src="libtest.png" width="100%"/>
 //
 // This file shows all the parts in the library.
 //
@@ -30,10 +47,12 @@ use <tests/bulldogs.scad>
 use <tests/buttons.scad>
 use <tests/cable_strips.scad>
 use <tests/cameras.scad>
+use <tests/camera_housing.scad>
 use <tests/circlips.scad>
 use <tests/components.scad>
 use <tests/d_connectors.scad>
 use <tests/displays.scad>
+use <tests/drag_chain.scad>
 use <tests/extrusions.scad>
 use <tests/extrusion_brackets.scad>
 use <tests/fans.scad>
@@ -50,6 +69,7 @@ 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>
@@ -58,6 +78,7 @@ use <tests/opengrab.scad>
 use <tests/panel_meters.scad>
 use <tests/PCBs.scad>
 use <tests/pillars.scad>
+use <tests/press_fit.scad>
 use <tests/PSUs.scad>
 use <tests/pulleys.scad>
 use <tests/rails.scad>
@@ -67,13 +88,14 @@ use <tests/rod.scad>
 use <tests/screws.scad>
 use <tests/SCS_bearing_blocks.scad>
 use <tests/sealing_strip.scad>
+use <tests/shaft_couplings.scad>
 use <tests/sheets.scad>
 use <tests/SK_brackets.scad>
 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>
@@ -116,17 +138,20 @@ cable_grommets_y = 0;
 translate([x5, cable_grommets_y])
     cable_grommets();
 
-translate([x5, cable_grommets_y + 50])
-    feet();
+translate([x5 + 50, cable_grommets_y])
+    ribbon_clamps();
 
-translate([x5, cable_grommets_y + 75])
+translate([x5 + 95, cable_grommets_y])
+    press_fits();
+
+translate([x5, cable_grommets_y + 60])
     fixing_blocks();
 
-translate([x5, cable_grommets_y + 100])
+translate([x5, cable_grommets_y + 90])
     corner_blocks();
 
 translate([x5, cable_grommets_y + 150])
-    ribbon_clamps();
+    feet();
 
 translate([x5 + 70, cable_grommets_y + 150])
     screw_knobs();
@@ -271,8 +296,9 @@ 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;
@@ -288,6 +314,9 @@ translate([x2 + 35, leds_y])
 translate([x2 + 8, carriers_y])
     carriers();
 
+translate([x2, magnets_y])
+    magnets();
+
 translate([x2 + 20, carriers_y])
     led_meters();
 
@@ -341,6 +370,9 @@ translate([x3 + 170, veroboard_y + 16])
 translate([x3, d_connectors_y])
     d_connectors();
 
+translate([x3 + 170, d_connectors_y - 10])
+    camera_housings();
+
 translate([x3, iecs_y])
     iecs();
 
@@ -385,17 +417,21 @@ 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])
         opengrab_test();
+
 }
 
+translate([x4 + 175, belts_y, -20])
+    drag_chains();
+
 translate([x4, rails_y + 130])
     rails();
 
-translate([800, fans_y + 50])
+translate([770, fans_y + 50])
     cable_strips();
 
 translate([x4, kp_pillow_blocks_y])
@@ -407,6 +443,9 @@ translate([x4, sk_brackets_y])
 translate([x4, extrusion_brackets_y])
     extrusion_brackets();
 
+translate([x4 + 120, extrusion_brackets_y])
+    shaft_couplings();
+
 translate([x4, scs_bearing_blocks_y])
     scs_bearing_blocks();
 

printed/box.scad

@@ -121,11 +121,12 @@ module grill(width, height, r = 1000, poly = false, h = 0) { //! A staggered arr
 
 module box_corner_profile_2D(type) { //! The 2D shape of the corner profile.
     t = box_sheet_slot(type);
+    inset = box_corner_gap(type) + box_profile_overlap(type);
     difference() {
         union() {
             quadrant(box_hole_inset(type) + box_boss_r(type), box_boss_r(type));     // inside corner
 
-            translate([box_corner_gap(type) + box_profile_overlap(type), box_corner_gap(type) + box_profile_overlap(type)])
+            translate([inset, inset])
                 rotate(180)
                     quadrant(box_profile_overlap(type) + box_corner_rad(type), box_corner_rad(type)); // outside corner
         }
@@ -212,33 +213,39 @@ module box_bezel(type, bottom) { //! Generates top and bottom bezel STLs
     feet = bottom && box_feet(type);
     t = box_sheet_slot(type);
     outset =  box_outset(type);
+    inset = box_inset(type);
     inner_r = box_sheet_r(type);
-    foot_height = box_corner_gap(type) + sheet_thickness(box_base_sheet(type)) + washer_thickness(box_washer(type)) + screw_head_height(box_screw(type)) + box_profile_overlap(type) + 2;
+    cgap = box_corner_gap(type);
+    foot_height = cgap + sheet_thickness(box_base_sheet(type)) + washer_thickness(box_washer(type)) + screw_head_height(box_screw(type)) + box_profile_overlap(type) + 2;
     foot_length = box_corner_rad(type) * 2;
     height = box_bezel_height(type, bottom);
     foot_extension = foot_height - height;
 
     difference() {
+        w = box_width(type);
+        d = box_depth(type);
         translate_z(-box_profile_overlap(type)) difference() {
-            rounded_rectangle([box_width(type) + 2 * outset, box_depth(type) + 2 * outset, feet ? foot_height : height], box_corner_rad(type), false);
+            tw = w + 2 * outset;
+            td = d + 2 * outset;
+            rounded_rectangle([tw, td, feet ? foot_height : height], box_corner_rad(type), false);
             //
             // Remove edges between the feet
             //
             if(feet)
                 hull() {
                     translate_z(height + 0.5)
-                        cube([box_width(type) - 2 * foot_length, box_depth(type) + 2 * outset + 1, 1], center = true);
+                        cube([w - 2 * foot_length, td + 1, 1], center = true);
 
                     translate_z(foot_height + 1)
-                        cube([box_width(type) - 2 * (foot_length - foot_extension), box_depth(type) + 2 * outset + 1, 1], center = true);
+                        cube([w - 2 * (foot_length - foot_extension), td + 1, 1], center = true);
                 }
             if(feet)
                 hull() {
                     translate_z(height + 0.5)
-                        cube([box_width(type) + 2 * outset + 1, box_depth(type) - 2 * foot_length, 1], center = true);
+                        cube([tw + 1, d - 2 * foot_length, 1], center = true);
 
                     translate_z(foot_height + 1)
-                        cube([box_width(type) + 2 * outset + 1, box_depth(type) - 2 * (foot_length - foot_extension), 1], center = true);
+                        cube([tw + 1, d - 2 * (foot_length - foot_extension), 1], center = true);
                 }
         }
         //
@@ -247,28 +254,28 @@ module box_bezel(type, bottom) { //! Generates top and bottom bezel STLs
         translate_z(-box_profile_overlap(type))
             linear_extrude(2 * box_profile_overlap(type), center = true)
                 for(i = [-1, 1]) {
-                    translate([i * (box_width(type) / 2 + t / 2 - sheet_slot_clearance / 2), 0])
-                         square([t, box_depth(type) - 2 * box_corner_gap(type)], center = true);
+                    translate([i * (w + t - sheet_slot_clearance) / 2, 0])
+                         square([t, d - 2 * cgap], center = true);
 
-                    translate([0, i * (box_depth(type) / 2 + t / 2 - sheet_slot_clearance / 2)])
-                         square([box_width(type) - 2 * box_corner_gap(type), t], center = true);
+                    translate([0, i * (d + t - sheet_slot_clearance) / 2])
+                         square([w - 2 * cgap, t], center = true);
                 }
         //
         // recess for top / bottom panel
         //
-        translate_z(box_corner_gap(type))
-            rounded_rectangle([box_width(type) + bezel_clearance, box_depth(type) + bezel_clearance, height], inner_r + bezel_clearance / 2, false);
+        translate_z(cgap)
+            rounded_rectangle([w + bezel_clearance, d + bezel_clearance, height], inner_r + bezel_clearance / 2, false);
         //
         // leave plastic over the corner profiles
         //
         translate_z(-box_profile_overlap(type) - 1)
-            linear_extrude(box_profile_overlap(type) + box_corner_gap(type) + 2)
+            linear_extrude(box_profile_overlap(type) + cgap + 2)
                 union() {
                     difference() {
-                        square([box_width(type) - 2 * box_inset(type),
-                                box_depth(type) - 2 * box_inset(type)], center = true);
+                        square([w - 2 * inset,
+                                d - 2 * inset], center = true);
 
-                        box_corner_quadrants(type, box_width(type), box_depth(type));
+                        box_corner_quadrants(type, w, d);
                     }
                     box_screw_hole_positions(type)
                         poly_circle(screw_clearance_radius(box_screw(type)));
@@ -291,7 +298,9 @@ module box_bezel_section(type, bottom, rows, cols, x, y) { //! Generates interlo
     dw = bw - 2 * dowel_wall;
     dh = box_bezel_height(type, bottom) - dowel_h_wall;
 
-    dh2 = box_profile_overlap(type) + box_corner_gap(type) - dowel_h_wall;
+    profile_overlap = box_profile_overlap(type);
+
+    dh2 = profile_overlap + box_corner_gap(type) - dowel_h_wall;
 
     end_clearance = 0.5;
     module male() {
@@ -299,14 +308,14 @@ module box_bezel_section(type, bottom, rows, cols, x, y) { //! Generates interlo
             linear_extrude(dowel_length - 2 * end_clearance, center = true)
                 difference() {
                     union() {
-                        h = dh - layer_height;
+                        h1 = dh - layer_height;
                         h2 = dh2 - layer_height;
                         hull() {
-                            translate([bw / 2, h / 2])
-                                square([dw - 1, h], center = true);
+                            translate([bw / 2, h1 / 2])
+                                square([dw - 1, h1], center = true);
 
-                            translate([bw / 2, (h - 1) / 2])
-                                square([dw, h - 1], center = true);
+                            translate([bw / 2, (h1 - 1) / 2])
+                                square([dw, h1 - 1], center = true);
                         }
 
                         hull() {
@@ -318,7 +327,7 @@ module box_bezel_section(type, bottom, rows, cols, x, y) { //! Generates interlo
                         }
                     }
                     translate([bw2 / 2, 0])
-                        square([box_sheet_slot(type), 2 * box_profile_overlap(type)], center = true);
+                        square([box_sheet_slot(type), 2 * profile_overlap], center = true);
                 }
     }
 
@@ -359,7 +368,7 @@ 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([tw / 2 - x * w, th / 2 - y * h, box_profile_overlap(type)])
+                    translate([tw / 2 - x * w, th / 2 - y * h, profile_overlap])
                         box_bezel(type, bottom);
 
                 if(x < cols - 1 && y == 0)
@@ -419,10 +428,14 @@ module box_bezel_section(type, bottom, rows, cols, x, y) { //! Generates interlo
     }
 }
 
-module box_screw_hole_positions(type)
+module box_screw_hole_positions(type) {
+    inset = box_hole_inset(type);
+    w = box_width(type) / 2 - inset;
+    d = box_depth(type) / 2 - inset;
     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))])
+        translate([x * w, y * d])
             children();
+}
 
 module box_base_blank(type) { //! Generates a 2D template for the base sheet
     dxf("box_base");

printed/camera_housing.scad

@@ -0,0 +1,392 @@
+//
+// 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/>.
+//
+
+//
+//! Housings for PCB cameras.
+//
+include <../core.scad>
+include <../vitamins/cameras.scad>
+use <../vitamins/pcb.scad>
+use <../vitamins/insert.scad>
+
+wall = 1.75;
+min_wall = 2 * extrusion_width;
+clearance = 0.2;
+
+connector_size = [23, 6, 2.65]; // Worst case size of flat flex connector
+
+cam_back_clearance = round_to_layer(1.5);    // Clearance for components on the back of the pcb
+cam_back_overlap = 1;                        // How much the back overlaps the edge of the pcb
+cam_back_wall = min_wall;
+
+function cam_front_clearance(cam) = round_to_layer(camera_connector_size(cam).z + clearance);
+
+function cam_back_size(cam) = let(
+    pcb = camera_pcb(cam),
+    pcb_size = pcb_size(pcb),
+    nut = screw_nut(pcb_screw(pcb)),
+    holes = [for(h = pcb_holes(pcb)) pcb_coord(pcb, h).x],
+    pitch = max(holes) - min(holes),
+    length = pitch + 2 * (nut_radius(nut) + min_wall),
+    width = pcb_size.y + (length - pcb_size.x) * cos(30)
+    ) [length, width, wall + max(connector_size.z, cam_back_clearance + nut_trap_depth(nut))];
+
+
+function cam_front_size(cam) = cam_back_size(cam) + [ //! Outside dimensions of the case
+    2 * (wall + clearance),
+    2 * (wall + clearance),
+    pcb_thickness(camera_pcb(cam)) + cam_front_clearance(cam) + wall
+];
+
+hinge_screw = M2_cap_screw;
+hinge_nut = screw_nut(hinge_screw);
+hinge_screw_length = 12;
+
+hinge_r = nut_trap_radius(hinge_nut) + 3 * extrusion_width;
+hinge_h = wall + nut_trap_depth(hinge_nut);
+hinge_offset = hinge_r + 1;
+
+bracket_screw = M3_dome_screw;
+
+function cam_screw_length(cam) = let(
+    front = cam_front_size(cam),
+    screw = pcb_screw(camera_pcb(cam)),
+    nut = screw_nut(screw)
+    ) screw_longer_than(front.z + washer_thickness(screw_washer(screw)) - nut_trap_depth(nut) + nut_thickness(nut, true));
+
+function hinge_z(cam) = cam_screw_length(cam) - hinge_r;
+
+module cam_holes(cam) {
+    pcb = camera_pcb(cam);
+    lens_y = camera_lens_offset(cam).y;
+    two_holes = !!len([for (h = pcb_holes(pcb)) if(abs(pcb_coord(pcb, h).y - lens_y) < 1) true]);
+    pcb_screw_positions(pcb)                                                    // screw holes
+        if($i > 1 || !two_holes)
+            children();
+}
+
+module rpi_camera_focus_ring_stl() { //! Focus ring the glue onto RPI lens
+    stl("rpi_camera_focus_ring");
+
+    rad = 15 / 2;
+    hole_r1 = 2.5 / 2;
+    hole_r2 = 5 / 2;
+    thickness = 3;
+    flutes = 8;
+    angle = 180 / flutes;
+    x = rad / (sin(angle / 2) + cos(angle / 2));
+    r = x * sin(angle / 2);
+
+    difference() {
+        linear_extrude(height = thickness, convexity = 5)
+            difference() {
+                union() {
+                    circle(x);
+                    for(i = [0 : flutes - 1])
+                        rotate([0, 0, 2 * angle * i])
+                            translate([x, 0])
+                                circle(r);
+                }
+                for(i = [0 : flutes - 1])
+                    rotate([0, 0, 2 * angle * i + angle])
+                        translate([x, 0])
+                            circle(r);
+            }
+        hull() {
+            poly_cylinder(r = hole_r1, h = 0.1, center = true);
+
+            translate([0, 0, thickness])
+                poly_cylinder(r = hole_r2, h = 0.1, center = true);
+        }
+    }
+}
+
+module camera_back(cam) { //! Make the STL for a camera case back
+    stl(str("camera_back_", cam[0]));
+    pcb = camera_pcb(cam);
+    back = cam_back_size(cam);
+    screw = pcb_screw(pcb);
+    nut = screw_nut(screw);
+
+    translate_z(back.z)
+        hflip()
+            difference() {
+                translate_z(back.z / 2)
+                    cube(back, center = true);
+
+                translate([0, -cam_back_overlap])
+                    cube([pcb_length(pcb) - 2 * cam_back_overlap, pcb_width(pcb), 2 * cam_back_clearance], center = true);
+
+                translate([0, -pcb_width(pcb) / 2])
+                    cube([connector_size.x + 2 * clearance, 2 * connector_size.y + 1, 2 * round_to_layer(connector_size.z + clearance)], center = true);
+
+                translate_z(back.z)
+                    cam_holes(cam)
+                        hflip()
+                            nut_trap(screw, nut, supported = true);
+            }
+}
+
+module camera_front(cam, hinge = 0) { //! Make the STL for a camera case front
+    stl(str("camera_front_", cam[0]));
+    front = cam_front_size(cam);
+    back = cam_back_size(cam);
+    pcb = camera_pcb(cam);
+    pcb_size = pcb_size(pcb);
+    lens_offset = camera_lens_offset(cam);
+    screw = pcb_screw(pcb);
+
+    shelf = front.z - back.z;
+
+    connector_slot = connector_size + 2 * [clearance, 0, layer_height];
+    rad = wall;
+    led_hole_r = 1;
+    led_clearance = [5,   2, 1 * 2];
+    res_clearance = [3.5, 2, 1 * 2];
+
+    conn_pos = camera_connector_pos(cam);
+    conn = camera_connector_size(cam);
+    sensor_length = conn_pos.y + conn.y / 2 - lens_offset.y + clearance;
+
+    module hinge_pos()
+        if(!is_undef(hinge))
+            rotate(hinge * 90)
+                translate([0, (hinge ? front.x * hinge : front.y) / 2 + hinge_offset, hinge_r])
+                    children();
+
+    difference() {
+        union() {
+            hull()
+                for(x = [-1, 1], y = [-1, 1])
+                    translate([x * (front.x / 2 - rad), y * (front.y / 2 - rad)])
+                        hull() {    // 3D truncated teardrop gives radiused edges without exceeding 45 degree overhang
+                            translate_z(front.z - 1)
+                                cylinder(r = rad, h = 1);
+
+                            translate_z(rad)
+                                sphere(rad);
+
+                            cylinder(r = rad * (sqrt(2) - 1), h = eps);
+                        }
+
+            hinge_pos()
+                hull() {
+                    rotate([-90, 0, -90])
+                        teardrop(r = hinge_r, h = hinge_h, center = false);
+
+                    translate([0, -10, -hinge_r])
+                        cube([hinge_h, eps, 2 * hinge_r]);
+                }
+        }
+
+        hinge_pos()
+            rotate([90, 0, 90])
+                teardrop_plus(r = screw_clearance_radius(hinge_screw), h = 100, center = true);
+
+        translate_z(front.z / 2 + shelf - layer_height)                                 // recess for the back
+            cube([back.x + 2 * clearance, back.y + 2 * clearance, front.z], center = true);
+
+        translate_z(front.z / 2 + shelf - pcb_size.z)                                   // recess for PCB
+            cube([pcb_size.x + 2 * clearance, pcb_size.y + 2 * clearance, front.z], center = true);
+
+        translate_z(shelf)
+            hflip() {
+                pcb_component_position(pcb, "smd_led")                                  // clearance for LED
+                    cube(led_clearance, center = true);
+
+                pcb_component_position(pcb, "smd_res")                                  // clearance for resistor
+                    cube(res_clearance, center = true);
+            }
+
+        translate([conn_pos.x, lens_offset.y + sensor_length / 2, shelf - pcb_size.z])  // clearance for sensor connector
+            cube([conn.x + 2 * clearance, sensor_length, 2 * cam_front_clearance(cam)], center = true);
+
+        translate([0, -front.y / 2, shelf + front.z / 2])                               // slot for connector
+            cube([connector_slot.x, connector_slot.y, front.z], center = true);
+
+        translate_z(cam_back_clearance + layer_height)
+            cam_holes(cam)
+                rotate(90)
+                    poly_cylinder(r = screw_clearance_radius(screw), h = 100, center = true);
+
+        translate_z(shelf - pcb_size.z)
+            hflip()
+                camera_lens(cam, clearance);
+
+        hflip()
+            pcb_component_position(pcb, "smd_led")
+                rotate(45)
+                    poly_cylinder(r = led_hole_r, h = 100, center = true);              // hole for led
+    }
+}
+
+function bracket_thickness(cam) = max(wall, min(3.5, hinge_z(cam) - hinge_r - 1));
+
+module camera_bracket_screw_positions(cam) { //! Position children at the bracket screw positions
+    r = washer_radius(screw_washer(bracket_screw)) + 0.5;
+    wide = bracket_thickness(cam) == wall;
+    pitch = wide ? cam_front_size(cam).x / 2 - r : hinge_h + 1 + r;
+
+    for(side = [-1, 1])
+        translate([side * pitch, 0])
+            children();
+}
+
+module camera_bracket_position(cam) //! Position children at the bracket position
+    translate([0,  cam_front_size(cam).y / 2 + hinge_offset])
+        children();
+
+module camera_bracket(cam) { //! Make the STL for the camera bracket
+    stl(str("camera_bracket_", cam[0]));
+
+    t = bracket_thickness(cam);
+    z = hinge_z(cam);
+    translate([hinge_h / 2, 0])
+        difference() {
+            hull() {
+                translate_z(eps / 2)
+                    cube([hinge_h, 2 * hinge_r, eps], center = true);
+
+                translate_z(z)
+                    rotate([0, 90, 0])
+                        cylinder(r = hinge_r, h = hinge_h, center = true);
+            }
+            translate([hinge_h / 2, 0, z])
+                rotate([90, 0, 90])
+                    nut_trap(hinge_screw, screw_nut(hinge_screw), horizontal = true);
+        }
+
+    linear_extrude(t)
+        difference() {
+            hull()
+                camera_bracket_screw_positions(cam)
+                    circle(washer_radius(screw_washer(bracket_screw)) + 0.5);
+
+            camera_bracket_screw_positions(cam)
+                poly_circle(screw_clearance_radius(bracket_screw));
+        }
+}
+
+module camera_assembly(cam, angle = 0) //! Camera case assembly
+assembly(str("camera_", cam[0])) {
+    front = cam_front_size(cam);
+    screw = pcb_screw(camera_pcb(cam));
+    nut = screw_nut(screw);
+    screw_length = cam_screw_length(cam);
+    hinge_z = hinge_z(cam);
+    hinge_pos = [0, front.y / 2  + hinge_offset, -hinge_r];
+
+    camera_bracket_position(cam) {
+        nut = screw_nut(hinge_screw);
+
+        stl_colour(pp1_colour) render()
+            camera_bracket(cam);
+
+        translate([-hinge_h, 0, hinge_z(cam)])
+            rotate([-90, 0, 90]) {
+                vflip()
+                    translate_z(2 * hinge_h - nut_trap_depth(nut))
+                        nut(nut, true);
+
+                screw_and_washer(hinge_screw, screw_longer_than(2 * hinge_h));
+            }
+    }
+
+    translate_z(hinge_z(cam) + hinge_r)
+        translate(hinge_pos)
+            rotate([-angle, 0, 0])
+                translate(-hinge_pos) {
+                    translate_z(cam_back_size(cam).z - front.z)
+                        camera(cam);
+
+                    stl_colour(pp1_colour) render()
+                        translate_z(-front.z)
+                            camera_back(cam);
+
+                    cam_holes(cam) {
+                        screw_and_washer(screw, screw_length);
+
+                        translate_z(-front.z + nut_trap_depth(nut))
+                            vflip()
+                                nut(nut, true);
+                    }
+
+                    *translate(camera_lens_offset(cam))
+                        translate_z(1.5)
+                            stl_colour(pp1_colour) render()
+                                rpi_camera_focus_ring_stl();
+
+                    stl_colour(pp2_colour) render()
+                        hflip()
+                            camera_front(cam, 0);
+                }
+}
+
+module camera_fastened_assembly(cam, thickness, angle = 0) {
+    camera_assembly(cam, angle);
+
+    camera_bracket_position(cam)
+        camera_bracket_screw_positions(cam) {
+            nut = screw_nut(bracket_screw);
+            washer = screw_washer(bracket_screw);
+            t = bracket_thickness(cam);
+            screw_length = screw_longer_than(thickness + t + nut_thickness(nut, true) + 2 * washer_thickness(washer));
+            vflip()
+                translate_z(thickness)
+                    screw_and_washer(bracket_screw, screw_length);
+
+            translate_z(t)
+                nut_and_washer(nut, true);
+        }
+}
+
+module camera_back_rpi_camera_stl()    camera_back(rpi_camera);
+module camera_back_rpi_camera_v1_stl() camera_back(rpi_camera_v1);
+module camera_back_rpi_camera_v2_stl() camera_back(rpi_camera_v2);
+
+module camera_front_rpi_camera_stl()    camera_front(rpi_camera);
+module camera_front_rpi_camera_v1_stl() camera_front(rpi_camera_v1);
+module camera_front_rpi_camera_v2_stl() camera_front(rpi_camera_v2);
+
+module camera_bracket_rpi_camera_stl()    camera_bracket(rpi_camera);
+module camera_bracket_rpi_camera_v1_stl() camera_bracket(rpi_camera_v1);
+module camera_bracket_rpi_camera_v2_stl() camera_bracket(rpi_camera_v2);
+
+module camera_rpi_camera_assembly()    camera_assembly(rpi_camera);
+module camera_rpi_camera_v1_assembly() camera_assembly(rpi_camera_v1);
+module camera_rpi_camera_v2_assembly() camera_assembly(rpi_camera_v2);
+
+module camera_housing(cam) {
+    front = cam_front_size(cam);
+
+    camera_front(cam, 0);
+
+    translate([front.x, 0])
+        camera_back(cam);
+
+    translate([-front.x / 2 - 2 - hinge_r, 0])
+        rotate(90)
+            camera_bracket(cam);
+}
+
+cam = rpi_camera_v2;
+if($preview)
+    camera_fastened_assembly(cam, 3);
+else
+    camera_housing(cam);

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);
                }
     }
 }

printed/drag_chain.scad

@@ -0,0 +1,321 @@
+//
+// 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/>.
+//
+
+//
+//! Parametric cable drag chain to limit the bend radius of a cable run.
+//!
+//! Each link has a maximum bend angle of 45&deg;, so the mininium radius is proportional to the link length.
+//!
+//! The travel property is how far it can move in each direction, i.e. half the maximum travel if the chain is mounted in the middle of the travel.
+//!
+//! The ends can have screw lugs with four screw positions to choose from, specified by a list of two arrays of four bools.
+//! If none are enabled then a child object is expected to customise the end and this gets unioned with the blank end.
+//! If both ends are customised then two children are expected.
+//! Each child is called twice, once with ```$fasteners``` set to 0 to augment the STL and again with ```$fasteners``` set to 1 to add
+//! to the assembly, for example to add inserts.
+//
+
+include <../core.scad>
+use <../utils/horiholes.scad>
+use <../utils/maths.scad>
+
+clearance = 0.1;
+
+function drag_chain_name(type)        = type[0]; //! The name to allow more than one in a project
+function drag_chain_size(type)        = type[1]; //! The internal size and link length
+function drag_chain_travel(type)      = type[2]; //! X travel
+function drag_chain_wall(type)        = type[3]; //! Side wall thickness
+function drag_chain_bwall(type)       = type[4]; //! Bottom wall
+function drag_chain_twall(type)       = type[5]; //! Top wall
+function drag_chain_screw(type)       = type[6]; //! Mounting screw for the ends
+function drag_chain_screw_lists(type) = type[7]; //! Two lists of four bools to say which screws positions are used
+
+function drag_chain_clearance() = clearance; //! Clearance around joints.
+
+function drag_chain_radius(type) = //! The bend radius at the pivot centres
+    let(s = drag_chain_size(type))
+        s.x / 2 / sin(360 / 16);
+
+function drag_chain_z(type) = //! Outside dimension of a 180 bend
+    let(os = drag_chain_outer_size(type), s = drag_chain_size(type))
+        2 * drag_chain_radius(type) + os.z;
+
+function drag_chain(name, size, travel, wall = 1.6, bwall = 1.5, twall = 1.5, screw = M2_cap_screw, screw_lists = [[1,0,0,1],[1,0,0,1]]) = //! Constructor
+    [name, size, travel, wall, bwall, twall, screw, screw_lists];
+
+function drag_chain_outer_size(type) = //! Link outer dimensions
+    let(s = drag_chain_size(type), z = s.z + drag_chain_bwall(type) + drag_chain_twall(type))
+        [s.x + z, s.y + 4 * drag_chain_wall(type) + 2 * clearance, z];
+
+function screw_lug_radius(screw) = //! Radius of a screw lug
+    corrected_radius(screw_clearance_radius(screw)) + 3.1 * extrusion_width;
+
+module screw_lug(screw, h = 0) //! Create a D shaped lug for a screw
+    extrude_if(h, center = false)
+        difference() {
+            r = screw_lug_radius(screw);
+            hull() {
+                circle4n(r);
+
+                translate([-r, -r])
+                    square([2 * r, eps]);
+            }
+            poly_circle(screw_clearance_radius(screw));
+        }
+
+function bool2int(b) = b ? 1 : 0;
+
+module drag_chain_screw_positions(type, end) { //! Place children at the screw positions, end = 0 for the start, 1 for the end
+    r = screw_lug_radius(drag_chain_screw(type));
+    s = drag_chain_size(type);
+    os = drag_chain_outer_size(type);
+    R = os.z / 2;
+    x0 = end ? R + norm([drag_chain_cam_x(type), R - drag_chain_twall(type)]) + clearance + r : r;
+    x1 = end ? os.x - r : os.x - 2 * R - clearance - r;
+    for(i = [0 : 3], x = [x0, x1, x0, x1][i], y = [-1, -1, 1, 1][i])
+        if(drag_chain_screw_lists(type)[bool2int(end)][i])
+            translate([x, y * (s.y / 2 + r)])
+                let($a = [180, 0, 180, 0][i])
+                    children();
+}
+
+function drag_chain_cam_x(type) = // how far the cam sticks out
+    let(s = drag_chain_size(type),
+        r =  drag_chain_outer_size(type).z / 2,
+        wall =  drag_chain_wall(type),
+        cam_r = s.x - 2 * clearance - wall - r,  // inner_x_normal - clearance - r
+        twall = drag_chain_twall(type)
+    )   min(sqrt(max(sqr(cam_r) - sqr(r - twall), 0)), r);
+
+module drag_chain_link(type, start = false, end = false, check_kids = true) { //! One link of the chain, special case for start and end
+    stl(str(drag_chain_name(type), "_drag_chain_link", start ? "_start" : end ? "_end" : ""));
+
+    s = drag_chain_size(type);
+    wall = drag_chain_wall(type);
+    bwall = drag_chain_bwall(type);
+    twall = drag_chain_twall(type);
+    os = drag_chain_outer_size(type);
+    r = os.z / 2;
+    pin_r = r / 2;
+
+    socket_x = r;
+    pin_x = socket_x + s.x;
+
+    outer_normal_x =  pin_x - r - clearance;     // s.x - clearance
+    outer_end_x = end ? os.x : outer_normal_x;
+
+    inner_x = start ? 0 : outer_normal_x - wall; // s.x - clearance - wall
+
+    roof_x_normal = 2 * r - twall;
+    roof_x = start ? 0 : roof_x_normal;
+
+    floor_x = start ? 0 : 2 * r;
+    cam_x = drag_chain_cam_x(type);
+    assert(r + norm([drag_chain_cam_x(type), r - drag_chain_twall(type)]) + clearance <= inner_x || start, "Link must be longer");
+
+    difference() {
+        union() {
+            for(side = [-1, 1])
+                rotate([90, 0, 0]) {
+                    // Outer cheeks
+                    translate_z(side * (os.y / 2 - wall / 2))
+                        linear_extrude(wall, center = true)
+                            difference() {
+                                hull() {
+                                    if(start)
+                                        square([eps, os.z]);
+                                    else
+                                        translate([socket_x, r])
+                                            rotate(180)
+                                                teardrop(r = r, h = 0);
+
+                                    translate([outer_end_x - eps, 0])
+                                        square([eps, os.z]);
+                                }
+                                if(!start)
+                                    translate([socket_x, r])
+                                        horihole(pin_r, r);
+                            }
+                    // Inner cheeks
+                    translate_z(side * (s.y / 2 + wall / 2))
+                        linear_extrude(wall, center = true)
+                            difference() {
+                                union() {
+                                    hull() {
+                                        if(!end) {
+                                            translate([pin_x, r])
+                                                rotate(180)
+                                                    teardrop(r = r, h = 0);
+
+                                            translate([pin_x, twall])
+                                                square([cam_x, eps]);
+                                        }
+                                        else
+                                            translate([os.x - eps, 0])
+                                                square([eps, os.z]);
+
+                                        translate([inner_x, 0])
+                                            square([eps, os.z]);
+                                    }
+                                }
+                                // Cutout for top wall
+                                if(!end)
+                                    intersection() {
+                                        translate([pin_x - r, 0])
+                                            square([3 * r, twall]);  // When straight
+
+                                        translate([pin_x, r])
+                                             rotate(-45)
+                                                translate([-r + roof_x_normal, -r - twall]) // When bent fully
+                                                    square(os.z);
+                                    }
+                            }
+                    // Pin
+                    if(!end)
+                        translate([pin_x, r, side * (s.y / 2 + wall + clearance)])
+                            horicylinder(r = pin_r, z = r, h = 2 * wall);
+
+                    // Cheek joint
+                    translate([inner_x, 0, side * (s.y / 2 + wall) - 0.5])
+                        cube([outer_end_x - inner_x, os.z, 1]);
+                }
+
+            // Roof, actually the floor when printed
+            roof_end = end ? s.x + 2 * r : s.x + r - twall - clearance;
+            translate([roof_x, -s.y / 2 - 0.5])
+                cube([roof_end - roof_x , s.y + 1, twall]);
+
+            translate([roof_x, -os.y / 2 + 0.5])
+                cube([s.x - clearance - roof_x, os.y - 1, twall]);
+
+            // Floor, actually the roof when printed
+            floor_end = end ? s.x + 2 * r : s.x + r;
+            translate([floor_x, -s.y / 2 - wall, os.z - bwall])
+                cube([floor_end - floor_x, s.y + 2 * wall, bwall]);
+
+            translate([floor_x, -os.y / 2 + 0.5,  os.z - bwall])
+                cube([s.x - floor_x - clearance, os.y -1, bwall]);
+
+            if(start || end) {
+                drag_chain_screw_positions(type, end)
+                    rotate($a)
+                        screw_lug(drag_chain_screw(type), os.z);
+
+                if(check_kids) {
+                    custom = drag_chain_screw_lists(type)[bool2int(end)] == [0, 0, 0, 0];
+                    assert($children == bool2int(custom), str("wrong number of children for ",  end ? "end" : "start", " STL customisation: ", $children));
+                }
+                children();
+            }
+        }
+        if(start || end)
+            translate_z(-eps)
+                drag_chain_screw_positions(type, end)
+                    rotate($a)
+                        poly_cylinder(r = screw_clearance_radius(drag_chain_screw(type)), h = os.z + 2 * eps, center = false);
+
+    }
+
+    if(show_supports() && !end) {
+        for(side = [-1, 1]) {
+            w = 2.1 * extrusion_width;
+            translate([s.x + r + cam_x - w / 2, side * (s.y / 2 + wall / 2), twall / 2])
+                cube([w, wall, twall], center = true);
+
+            h = round_to_layer(r - pin_r / sqrt(2));
+            y = s.y / 2  + max(wall + w / 2 + clearance, 2 * wall + clearance - w / 2);
+            translate([s.x + r, side * y, h / 2])
+                cube([pin_r * sqrt(2), w, h], center = true);
+
+            gap = cam_x - pin_r / sqrt(2) + extrusion_width;
+            translate([s.x + r + cam_x - gap / 2, side * (s.y / 2 + wall + clearance / 2), layer_height / 2])
+                cube([gap, 2 * wall + clearance, layer_height], center = true);
+        }
+    }
+}
+
+// Need to use a wrapper because can't define nested modules in an assembly
+module _drag_chain_assembly(type, pos = 0) {
+    s = drag_chain_size(type);
+    x = (1 + exploded()) * s.x;
+    r = drag_chain_radius(type) * x / s.x;
+    travel = drag_chain_travel(type);
+    links = ceil(travel / s.x);
+    actual_travel = links * s.x;
+    z = drag_chain_outer_size(type).z;
+
+    zb = z / 2;                                     // z of bottom track
+    c = [actual_travel / 2 + pos / 2, 0, r + zb];   // centre of bend
+
+    points = [                                      // Calculate list of hinge points
+        for(i = 0, p = [0, 0, z / 2 + 2 * r]; i < links + 5;
+            i = i + 1,
+            dx = p.z > c.z ? x : -x,
+            p = max(p.x + dx, p.x) <= c.x ? p + [dx, 0, 0]      // Straight sections
+                  : let(q = circle_intersect(p, x, c, r))
+                        q.x <= c.x ? [p.x - sqrt(sqr(x) - sqr(p.z - zb)), 0, zb] // Transition back to straight
+                                   : q) // Circular section
+        p
+    ];
+    npoints = len(points);
+
+    module link(n)                                  // Position and colour link with origin at the hinge hole
+        translate([-z / 2, 0, -z / 2]) {
+            stl_colour(n < 0 || n == npoints - 1 ? pp3_colour : n % 2 ? pp1_colour : pp2_colour)
+                drag_chain_link(type, start = n == -1, end = n == npoints - 1, check_kids = false)
+                    let($fasteners = 0) children();
+            let($fasteners = 1) children();
+        }
+
+    screws = drag_chain_screw_lists(type);
+    custom_start = screws[0] == [0, 0, 0, 0];
+    custom_end   = screws[1] == [0, 0, 0, 0];
+    assert($children == bool2int(custom_start) + bool2int(custom_end), str("wrong number of children for end customisation: ", $children));
+
+    for(i = [0 : npoints - 2]) let(v = points[i + 1] - points[i])
+        translate(points[i])
+            rotate([0, -atan2(v.z, v.x), 0])
+                link(i);
+
+    translate(points[0] - [x, 0, 0])
+        link(-1)
+            if(custom_start)
+                children(0);
+
+    translate(points[npoints - 1])
+        hflip()
+            link(npoints - 1)
+                if(custom_end)
+                    children(custom_start ? 1 : 0);
+}
+
+//! 1. Remove the support material from the links with side cutters.
+//! 1. Clip the links together with the special ones at the ends.
+module drag_chain_assembly(type, pos = 0)  //! Drag chain assembly
+    assembly(str(drag_chain_name(type), "_drag_chain"), big = true)
+        if($children == 2)
+            _drag_chain_assembly(type, pos) {
+                children(0);
+                children(1);
+            }
+        else if($children == 1)
+            _drag_chain_assembly(type, pos)
+                children(0);
+        else
+            _drag_chain_assembly(type, pos);

printed/press_fit.scad

@@ -0,0 +1,50 @@
+//
+// 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/>.
+//
+
+//
+//! Utility for making printed press fit connectors to join printed parts.
+//!
+//! Add solvent or glue to make a permanent fixture.
+//
+include <../core.scad>
+
+interference = 0.0;
+
+bridge_droop = layer_height; //sqrt(4 * layer_height * filament_width / PI) - layer_height;
+
+module press_fit_socket(w = 5, h = 50, horizontal = false) { //! Make a square hole to accept a peg
+    h = horizontal ? h : h + bridge_droop;
+
+    cube([w, w, 2 * h], center = true);
+}
+
+module press_fit_peg(h, w = 5, horizontal = false) {    //! Make a rounded chamfered peg for easy insertion
+    module chamfered_square(w, horizontal) {
+        h = horizontal ? w - bridge_droop : w;
+        rounded_square([w, h], 1);
+    }
+
+    translate_z(-eps)
+        linear_extrude(height = h + eps - layer_height)
+            chamfered_square(w + interference, horizontal);
+
+    translate_z(h - layer_height - eps)
+        linear_extrude(height = layer_height + eps)
+            chamfered_square(w - layer_height, horizontal);
+}

printed/ribbon_clamp.scad

@@ -24,69 +24,72 @@ include <../core.scad>
 use <../vitamins/insert.scad>
 use <../vitamins/cable_strip.scad>
 
-wall = 2;
+wall = 1.6;
 min_wall = 2 * extrusion_width;
 screw = M3_cap_screw;
-insert = screw_insert(screw);
-screw_depth = insert_length(insert) + 1;
 
-function ribbon_clamp_hole_pitch(ways) = ribbon_clamp_slot(ways) + 2 * min_wall + 2 * corrected_radius(insert_hole_radius(insert)); //! Hole pitch
-function ribbon_clamp_width() = 2 * (insert_hole_radius(insert) + wall); //! Width
-function ribbon_clamp_length(ways) = ribbon_clamp_hole_pitch(ways) + ribbon_clamp_width(); //! Length given ways
-function ribbon_clamp_height() = screw_depth + 1; //! Height
+function ribbon_clamp_screw_depth(screw = screw) = insert_length(screw_insert(screw)) + 1;
+function ribbon_clamp_hole_pitch(ways, screw = screw) =
+    ribbon_clamp_slot(ways) + 2 * min_wall + 2 * corrected_radius(insert_hole_radius(screw_insert(screw))); //! Hole pitch
 
-module ribbon_clamp_hole_positions(ways, side = undef) //! Place children at hole positions
+function ribbon_clamp_width(screw = screw) = 2 * (insert_hole_radius(screw_insert(screw)) + wall); //! Width
+function ribbon_clamp_length(ways, screw = screw) = ribbon_clamp_hole_pitch(ways, screw) + ribbon_clamp_width(screw); //! Length given ways
+function ribbon_clamp_height(screw = screw) = ribbon_clamp_screw_depth(screw) + 1; //! Height
+
+module ribbon_clamp_hole_positions(ways, screw = screw, side = undef) //! Place children at hole positions
     for(x = is_undef(side) ? [-1, 1] : side)
-        translate([x * ribbon_clamp_hole_pitch(ways) / 2, 0])
+        translate([x * ribbon_clamp_hole_pitch(ways, screw) / 2, 0])
             children();
 
-module ribbon_clamp_holes(ways, h = 20) //! Drill screw holes
-    ribbon_clamp_hole_positions(ways)
+module ribbon_clamp_holes(ways, h = 20, screw = screw) //! Drill screw holes
+    ribbon_clamp_hole_positions(ways, screw)
         drill(screw_clearance_radius(screw), h);
 
-module ribbon_clamp(ways) { //! Generate STL for given number of ways
-    stl(str("ribbon_clamp_", ways));
+module ribbon_clamp(ways, screw = screw) { //! Generate STL for given number of ways
+    screw_d = screw_radius(screw) * 2;
+    stl(str("ribbon_clamp_", ways, screw_d != 3 ? str("_", screw_d) : ""));
 
-    pitch = ribbon_clamp_hole_pitch(ways);
-    d = ribbon_clamp_width();
-    h = ribbon_clamp_height();
-    t = h - ribbon_clamp_slot_depth() - wall;
+    pitch = ribbon_clamp_hole_pitch(ways, screw);
+    d = ribbon_clamp_width(screw);
+    h = ribbon_clamp_height(screw);
+    t = round_to_layer(ribbon_clamp_slot_depth() + wall);
+    insert = screw_insert(screw);
 
     difference() {
         union() {
             hull() {
                 translate_z(h - t / 2)
-                    cube([ribbon_clamp_hole_pitch(ways), d, t], center = true);
+                    cube([ribbon_clamp_hole_pitch(ways, screw), d, t], center = true);
 
                 translate_z(1)
                     cube([pitch, max(wall, d - 2 * (h - t)), 2], center = true);
             }
-            ribbon_clamp_hole_positions(ways, -1)
+            ribbon_clamp_hole_positions(ways, screw, -1)
                 cylinder(d = d, h = h);
 
-            ribbon_clamp_hole_positions(ways,  1)
+            ribbon_clamp_hole_positions(ways, screw, 1)
                 cylinder(d = d, h = h);
-
         }
 
         translate_z(h)
             cube([ribbon_clamp_slot(ways), d + 1, ribbon_clamp_slot_depth() * 2], center = true);
 
-        ribbon_clamp_hole_positions(ways)
+        ribbon_clamp_hole_positions(ways, screw)
             translate_z(h)
                 rotate(22.5)
-                    insert_hole(insert, screw_depth - insert_length(insert));
+                    insert_hole(insert, ribbon_clamp_screw_depth(screw) - insert_length(insert));
     }
 }
 
-module ribbon_clamp_assembly(ways) pose([55, 180, 25])  //! Printed part with inserts in place
-    assembly(str("ribbon_clamp_", ways)) {
-    h = ribbon_clamp_height();
+module ribbon_clamp_assembly(ways, screw = screw) pose([55, 180, 25])  //! Printed part with inserts in place
+    assembly(let(screw_d = screw_radius(screw) * 2)str("ribbon_clamp_", ways, screw_d != 3 ? str("_", screw_d) : "")) {
+    h = ribbon_clamp_height(screw);
+    insert = screw_insert(screw);
 
     stl_colour(pp1_colour) render()
-        translate_z(h) vflip() ribbon_clamp(ways);
+        translate_z(h) vflip() ribbon_clamp(ways, screw);
 
-    ribbon_clamp_hole_positions(ways)
+    ribbon_clamp_hole_positions(ways, screw)
         vflip()
             insert(insert);
 }
@@ -99,20 +102,28 @@ module ribbon_clamp_fastened_assembly(ways, thickness, screw = screw) { //! Clam
     vitamin(str(": Tape self amalgamating silicone ",tape_l," x 25mm"));
 
     washer = screw_washer(screw);
-    screw_length = screw_shorter_than(2 * washer_thickness(washer) + thickness + screw_depth);
+    screw_length = screw_shorter_than(2 * washer_thickness(washer) + thickness + ribbon_clamp_screw_depth(screw));
 
-    ribbon_clamp_assembly(ways);
+    ribbon_clamp_assembly(ways, screw);
 
     color("red") translate_z(tape_thickness / 2)
         cube([tape_l, tape_width, tape_thickness], center = true);
 
-    ribbon_clamp_hole_positions(ways)
+    ribbon_clamp_hole_positions(ways, screw)
         vflip()
            translate_z(thickness)
                 screw_and_washer(screw, screw_length, true);
 }
 
 module ribbon_clamp_20_stl() ribbon_clamp(20);
+module ribbon_clamp_8_2_stl() ribbon_clamp(8, M2_dome_screw);
+module ribbon_clamp_7_2_stl() ribbon_clamp(8, M2_dome_screw);
 
 //! * Place inserts into the holes and press home with a soldering iron with a conical bit heated to 200&deg;C.
 module ribbon_clamp_20_assembly() ribbon_clamp_assembly(20);
+
+//! * Place inserts into the holes and press home with a soldering iron with a conical bit heated to 200&deg;C.
+module ribbon_clamp_8_2_assembly() ribbon_clamp_assembly(8, M2_dome_screw);
+
+//! * Place inserts into the holes and press home with a soldering iron with a conical bit heated to 200&deg;C.
+module ribbon_clamp_7_2_assembly() ribbon_clamp_assembly(8, M2_dome_screw);

scripts/plateup.py

@@ -87,24 +87,25 @@ def plateup(target, part_type, usage = None):
                     match = re.match(r'^ECHO: "~(.*?\.' + part_type + r').*"$', line)
                     if match:
                         used.append(match.group(1))
-    #
-    # Copy file that are not included
-    #
     copied = []
-    for file in os.listdir(parts_dir):
-        if file.endswith('.' + part_type) and not file in used:
-            src = parts_dir + '/' + file
-            dst = target_dir + '/' + file
-            if mtime(src) > mtime(dst):
-                print("Copying %s to %s" % (src, dst))
-                copyfile(src, dst)
-            copied.append(file)
-    #
-    # Remove any cruft
-    #
-    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:
-                print("Removing %s" % file)
-                os.remove(target_dir + '/' + file)
+    if all_sources:
+        #
+        # Copy files that are not included
+        #
+        for file in os.listdir(parts_dir):
+            if file.endswith('.' + part_type) and not file in used:
+                src = parts_dir + '/' + file
+                dst = target_dir + '/' + file
+                if mtime(src) > mtime(dst):
+                    print("Copying %s to %s" % (src, dst))
+                    copyfile(src, dst)
+                copied.append(file)
+        #
+        # Remove any cruft
+        #
+        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:
+                    print("Removing %s" % file)
+                    os.remove(target_dir + '/' + file)

scripts/tests.py

@@ -97,7 +97,6 @@ def tests(tests):
     for dir in [deps_dir, png_dir, bom_dir]:
         if not os.path.isdir(dir):
             os.makedirs(dir)
-    doc_name = "readme.md"
     index = {}
     bodies = {}
     done = []
@@ -108,19 +107,33 @@ def tests(tests):
     #
     png_name = "libtest.png"
     scad_name = "libtest.scad"
-    if not os.path.isfile(png_name):
-        openscad.run(colour_scheme, "--projection=p", "--imgsize=%d,%d" % (w, h), "--camera=0,0,0,50,0,340,500", "--autocenter", "--viewall", "-o", png_name, scad_name);
-        do_cmd(["magick", png_name, "-trim", "-resize", "1280", "-bordercolor", background, "-border", "10", png_name])
+    if os.path.isfile(scad_name):
+        libtest = True
+        lib_blurb = scrape_blurb(scad_name)
+        if not os.path.isfile(png_name):
+            openscad.run(colour_scheme, "--projection=p", "--imgsize=%d,%d" % (w, h), "--camera=0,0,0,50,0,340,500", "--autocenter", "--viewall", "-o", png_name, scad_name);
+            do_cmd(["magick", png_name, "-trim", "-resize", "1280", "-bordercolor", background, "-border", "10", png_name])
+    else:
+        #
+        # Project tests so just a title
+        #
+        libtest = False
+        project = ' '.join(word[0].upper() + word[1:] for word in os.path.basename(os.getcwd()).split('_'))
+        lib_blurb = '#' + project + ' Tests\n'
+
+    doc_base_name = "readme" if libtest else "tests"
+    doc_name = doc_base_name + ".md"
     #
     # List of individual part files
     #
-    scads = [i for i in sorted(os.listdir(scad_dir), key = lambda s: s.lower()) if i[-5:] == ".scad"]
 
+    scads = [i for i in sorted(os.listdir(scad_dir), key = lambda s: s.lower()) if i[-5:] == ".scad"]
+    types = []
     for scad in scads:
         base_name = scad[:-5]
         if not tests or base_name in tests:
             done.append(base_name)
-            print(base_name)
+            print('\n'+base_name)
             cap_name = base_name[0].capitalize() + base_name[1:]
             base_name = base_name.lower()
             scad_name = scad_dir + '/' + scad
@@ -132,29 +145,42 @@ def tests(tests):
             if is_plural(base_name) and os.path.isfile(vits_name):
                 objects_name = vits_name
 
-            locations = [
-                ('vitamins/' + depluralise(base_name) + '.scad', 'Vitamins'),
-                ('printed/' + base_name + '.scad',               'Printed'),
-                ('utils/' + base_name + '.scad',                 'Utilities'),
-                ('utils/core/' + base_name + '.scad',            'Core Utilities'),
-            ]
+            locations = []
+            if os.path.isdir('vitamins'):
+                locations.append(('vitamins/' + depluralise(base_name) + '.scad', 'Vitamins'))
+            if os.path.isdir('printed'):
+                locations.append(('printed/' + base_name + '.scad',               'Printed'))
+            if os.path.isdir('utils'):
+                locations.append(('utils/' + base_name + '.scad',                 'Utilities'))
+            if libtest and os.path.isdir('utils/core'):
+                locations.append(('utils/core/' + base_name + '.scad',            'Core Utilities'))
 
             for name, type in locations:
                 if os.path.isfile(name):
                     impl_name = name
                     break
             else:
-                print("Can't find implementation!")
-                continue
+                if libtest:
+                    print("Can't find implementation!")
+                    continue
+                else:
+                    type = 'Tests'                         # OK when testing part of a project
+                    impl_name = None
 
-            vsplit = "AJR" + chr(ord('Z') + 1)
-            vtype = locations[0][1]
-            types = [vtype + ' ' + vsplit[i] + '-'  + chr(ord(vsplit[i + 1]) - 1) for i in range(len(vsplit) - 1)] + [loc[1] for loc in locations[1 :]]
-            if type == vtype:
-                for i in range(1, len(vsplit)):
-                    if cap_name[0] < vsplit[i]:
-                         type = types[i - 1]
-                         break
+            if libtest:
+                vsplit = "AJR" + chr(ord('Z') + 1)
+                vtype = locations[0][1]
+                types = [vtype + ' ' + vsplit[i] + '-' + chr(ord(vsplit[i + 1]) - 1) for i in range(len(vsplit) - 1)] + [loc[1] for loc in locations[1 :]]
+                if type == vtype:
+                    for i in range(1, len(vsplit)):
+                        if cap_name[0] < vsplit[i]:
+                             type = types[i - 1]
+                             break
+            else:
+                if not types:
+                    types = [loc[1] for loc in locations]   # No need to split up the vitamin list
+                    if not type in types:                   # Will happen when implementation is not found and type is set to Tests
+                        types.append(type)
 
             for t in types:
                 if not t in bodies:
@@ -250,24 +276,7 @@ def tests(tests):
         usage()
 
     with open(doc_name, "wt") as doc_file:
-        print('# NopSCADlib', file = doc_file)
-        print('''\
-An ever expanding library of parts modelled in OpenSCAD useful for 3D printers and enclosures for electronics, etc.
-
-It contains lots of vitamins (the RepRap term for non-printed parts), some general purpose printed parts and
-some utilities. There are also Python scripts to generate Bills of Materials (BOMs),
- STL files for all the printed parts, DXF files for CNC routed parts in a project and a manual containing assembly
-instructions and exploded views by scraping markdown embedded in OpenSCAD comments, [see scripts](scripts/readme.md). A simple example project can be found [here](examples/MainsBreakOutBox/readme.md).
-
-For more examples of what it can make see the [gallery](gallery/readme.md).
-
-The license is GNU General Public License v3.0, see [COPYING](COPYING).
-
-See [usage](docs/usage.md) for requirements, installation instructions and a usage guide.
-
-<img src="libtest.png" width="100%"/>\n
-''', file = doc_file)
-
+        print(lib_blurb, file = doc_file)
         print('## Table of Contents<a name="top"/>', file = doc_file)
         print('<table><tr>', file = doc_file)
         n = 0
@@ -288,10 +297,10 @@ See [usage](docs/usage.md) for requirements, installation instructions and a usa
         for type in types:
             for line in bodies[type]:
                 print(line, file = doc_file)
-    with open("readme.html", "wt") as html_file:
-        do_cmd("python -m markdown -x tables readme.md".split(), html_file)
+    with open(doc_base_name + ".html", "wt") as html_file:
+        do_cmd(("python -m markdown -x tables " + doc_name).split(), html_file)
     times.print_times()
-    do_cmd('codespell -L od readme.md'.split())
+    do_cmd(('codespell -L od ' + doc_name).split())
 
 if __name__ == '__main__':
     for arg in sys.argv[1:]:

scripts/views.py

@@ -308,8 +308,7 @@ def views(target, do_assemblies = None):
                 if printed:
                     print('### 3D Printed parts', file = doc_file)
                     keys = sorted(list(printed.keys()))
-                    for i in range(len(keys)):
-                        p = keys[i]
+                    for i, p in enumerate(keys):
                         print('%s %d x %s |' % ('\n|' if not (i % 3) else '', printed[p]["count"], p), file = doc_file, end = '')
                         if (i % 3) == 2 or i == len(printed) - 1:
                             n = (i % 3) + 1
@@ -324,8 +323,7 @@ def views(target, do_assemblies = None):
                 if routed:
                     print("### CNC Routed parts", file = doc_file)
                     keys = sorted(list(routed.keys()))
-                    for i in range(len(keys)):
-                        r = keys[i]
+                    for i, r in enumerate(keys):
                         print('%s %d x %s |' % ('\n|' if not (i % 3) else '', routed[r]["count"], r), file = doc_file, end = '')
                         if (i % 3) == 2 or i == len(routed) - 1:
                             n = (i % 3) + 1
@@ -340,8 +338,7 @@ def views(target, do_assemblies = None):
                 if sub_assemblies:
                     print("### Sub-assemblies", file = doc_file)
                     keys = sorted(list(sub_assemblies.keys()))
-                    for i in range(len(keys)):
-                        a = keys[i]
+                    for i, a in enumerate(keys):
                         print('%s %d x %s |' % ('\n|' if not (i % 3) else '', sub_assemblies[a], a), file = doc_file, end = '')
                         if (i % 3) == 2 or i == len(keys) - 1:
                             n = (i % 3) + 1

tests/PCB.scad

@@ -86,10 +86,13 @@ 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)],
@@ -118,7 +121,8 @@ test_pcb = ["TestPCB", "Test PCB",
         [ 70, 130, 180, "term35", 3, "lime"],
         [ 50, 150,   0, "transition", 5],
         [ 50, 160,   0, "block", 10, 5, 8, "orange"],
-        [ 50, 170,   0, "button_6mm"],
+        [ 45, 170,   0, "button_6mm"],
+        [ 55, 170,   0, "button_4p5mm"],
         [ 50, 185,   0, "microswitch", small_microswitch],
         [ 52, 200,   0, "pcb", 11, TMC2130 ],
         [ 80, 200,   0, "pdip", 24, "27C32", true, inch(0.6) ],

tests/belts.scad

@@ -23,46 +23,52 @@ use <../vitamins/insert.scad>
 use <../utils/layout.scad>
 
 module belt_test() {
-    p1 = [75,  -50];
     p2 = [-75, -50];
     p3 = [-75, 100];
     p4 = [75,  100];
 
-    p5 = [75  - pulley_pr(GT2x20ob_pulley) - pulley_pr(GT2x16_plain_idler),  -pulley_pr(GT2x16_plain_idler)];
-    p6 = [-75 + pulley_pr(GT2x20ob_pulley) + pulley_pr(GT2x16_plain_idler),  -pulley_pr(GT2x16_plain_idler)];
+    p5 = [75  + pulley_pr(GT2x20ob_pulley) - pulley_pr(GT2x16_plain_idler), +pulley_pr(GT2x16_plain_idler)];
+    p6 = [-75 + pulley_pr(GT2x20ob_pulley) + pulley_pr(GT2x16_plain_idler), -pulley_pr(GT2x16_plain_idler)];
 
-    translate(p1) pulley_assembly(GT2x20ob_pulley);
-    translate(p2) pulley_assembly(GT2x20ob_pulley);
-    translate(p3) pulley_assembly(GT2x20_toothed_idler);
-    translate(p4) pulley_assembly(GT2x20_toothed_idler);
+    module pulleys(flip = false) {
+        translate(p2) rotate([0, flip ? 180 : 0, 0]) pulley_assembly(GT2x20ob_pulley);
+        translate(p3) pulley_assembly(GT2x20_toothed_idler);
+        translate(p4) pulley_assembly(GT2x20_toothed_idler);
+        translate(p5) {
+            pulley = GT2x16_toothed_idler;
+            screw = find_screw(hs_cs_cap, pulley_bore(pulley));
+            insert = screw_insert(screw);
 
-    translate(p5) {
-        pulley = GT2x16_plain_idler;
-        screw = find_screw(hs_cs_cap, pulley_bore(pulley));
-        insert = screw_insert(screw);
-
-        pulley_assembly(pulley);
-        translate_z(pulley_height(pulley) + pulley_offset(pulley) + screw_head_depth(screw, pulley_bore(pulley)))
-            screw(screw, 20);
-
-        translate_z(pulley_offset(pulley) - insert_length(insert))
-            vflip()
-                insert(insert);
+            hflip(flip) {
+                pulley_assembly(pulley);
+                translate_z(pulley_height(pulley) + pulley_offset(pulley) + screw_head_depth(screw, pulley_bore(pulley)))
+                    screw(screw, 20);
 
+                translate_z(pulley_offset(pulley) - insert_length(insert))
+                    vflip()
+                        insert(insert);
+            }
+        }
+        translate(p6) pulley_assembly(GT2x16_plain_idler);
     }
-    translate(p6) pulley_assembly(GT2x16_plain_idler);
 
-    path = [ [p1.x, p1.y, pulley_pr(GT2x20ob_pulley)],
-             [p5.x, p5.y, -pulley_pr(GT2x16_plain_idler)],
+    path = [ [p5.x, p5.y, pulley_pr(GT2x16_plain_idler)],
              [p6.x, p6.y, -pulley_pr(GT2x16_plain_idler)],
              [p2.x, p2.y, pulley_pr(GT2x20ob_pulley)],
              [p3.x, p3.y, pulley_pr(GT2x20ob_pulley)],
              [p4.x, p4.y, pulley_pr(GT2x20ob_pulley)]
            ];
-    belt = GT2x6;
-    belt(belt, path, 80, [0,  belt_pitch_height(belt) - belt_thickness(belt) / 2]);
 
-    translate([-25, 0])
+    belt = GT2x6;
+    belt(belt, path, 80, [0,  0]);
+    pulleys();
+    translate_z(20)
+        hflip() {
+            belt(belt, path, 80, [0,  0], belt_colour = grey(90), tooth_colour = grey(50));
+            pulleys(flip=true);
+        }
+
+    translate([-25, 0, 10])
         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 ? grey(90) : grey(20), tooth_colour = $i%2==0 ? grey(70) : grey(50));

tests/camera_housing.scad

@@ -0,0 +1,33 @@
+//
+// 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>
+
+use <../printed/camera_housing.scad>
+
+include <../vitamins/cameras.scad>
+
+use <../vitamins/pcb.scad>
+
+module camera_housings()
+    layout([for(c = cameras) pcb_length(camera_pcb(c))], 15, false) let(c = cameras[$i])
+        camera_fastened_assembly(c, 3);
+
+if($preview)
+    camera_housings();

tests/cameras.scad

@@ -24,7 +24,7 @@ include <../vitamins/cameras.scad>
 use <../vitamins/pcb.scad>
 
 module cameras()
-    layout([for(c = cameras) pcb_length(camera_pcb(c))], 10, false) let(c = cameras[$i])
+    layout([for(c = cameras) pcb_length(camera_pcb(c))], 15, false) let(c = cameras[$i])
         camera(c);
 
 if($preview)

tests/catenary.scad

@@ -0,0 +1,56 @@
+//
+// 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/>.
+//
+l = 250; // [1: 1000]
+x = 200; // [1: 1000]
+y = 50; //[-500 : 500]
+
+include <../utils/core/core.scad>
+use <../utils/catenary.scad>
+use <../utils/sweep.scad>
+use <../utils/annotation.scad>
+
+module catenaries() {
+    //
+    // catenary curve path from control points
+    //
+    curve = [for(p = catenary_points(l, x, y)) [p.x, p.y, 0]];
+    //
+    // Draw the curve
+    //
+    r = 0.5;
+    sweep(curve, circle_points(r, $fn = 64));
+    //
+    // Minimum Z
+    //
+    min_z = catenary_points(l, x, y, 0);
+
+    color("blue") {
+        translate([min_z.x, min_z.y + r])
+            rotate([-90, 0, 0])
+                arrow();
+
+        translate([min_z.x, min_z.y - r])
+            rotate([90, 0, 0])
+                arrow();
+    }
+}
+
+if($preview)
+    rotate(is_undef($bom) ? 0 : [70, 0, 315])
+        catenaries();

tests/dogbones.scad

@@ -26,6 +26,12 @@ module dogbones() {
     #translate([15, 0])
         dogbone_rectangle([10, 20, 5], center = false);
 
+    #translate([30, 0])
+        dogbone_rectangle_x([10, 20, 5], center = false);
+
+    #translate([45, 0])
+        dogbone_rectangle_y([10, 20, 5], center = false);
+
     sq = 3;
     translate([-5 + sq / 2 + eps, -10 + sq / 2 + eps])
         %cube([sq, sq, 1], center = true);

tests/drag_chain.scad

@@ -0,0 +1,59 @@
+//
+// 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/>.
+//
+
+// Link length between hinges
+x = 10; //[8 : 30]
+
+// Link inner width
+y = 10; //[5 : 30]
+
+// Link inner height
+z = 5;  //[4 : 11]
+// Side wall thickness
+wall = 1.6; //[0.9: 0.1: 3]
+// Bottom wall thickness
+bwall = 1.5; //[1: 0.25: 3]
+// Top wall thickness
+twall = 1.5; //[1: 0.25: 3]
+// Max travel in each direction
+travel = 100;
+// Current position
+pos = 50; // [-100 : 1 : 100]
+
+include <../core.scad>
+use <../printed/drag_chain.scad>
+
+include <../vitamins/leadnuts.scad>
+
+drag_chain = drag_chain("x", [x, y, z], travel, wall = wall, bwall = bwall, twall = twall);
+
+module drag_chains()
+    drag_chain_assembly(drag_chain, pos);
+
+if($preview)
+    drag_chains();
+else {
+    drag_chain_link(drag_chain);
+
+    translate([-x * 2, 0])
+        drag_chain_link(drag_chain, start = true);
+
+    translate([x * 2, 0])
+        drag_chain_link(drag_chain, end = true);
+}

tests/foot.scad

@@ -21,14 +21,14 @@ use <../printed/foot.scad>
 
 module feet()
     if($preview) {
-        translate([50, 0])
+        translate([40, 0])
             foot_assembly(3);
 
         translate([foot_diameter(insert_foot()) / 2, 0])
             fastened_insert_foot_assembly(3);
     }
     else {
-        translate([50, 0])
+        translate([40, 0])
             foot();
 
         insert_foot();

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();

tests/global.scad

@@ -29,6 +29,23 @@ module globals() {
         translate([50, 0])
             right_triangle(10, 20, 0);
     }
+    assert(slice("ABCD")    == "ABCD");
+    assert(slice("ABCD", 1) == "BCD");
+    assert(slice("ABCD", 2) == "CD");
+    assert(slice("ABCD", 3) == "D");
+    assert(slice("ABCD", 4) == "");
+    assert(slice("ABCD", 1, -1) == "BC");
+    assert(slice("ABCD", 2, -1) == "C");
+    assert(slice("ABCD", 3, -1) == "");
+    assert(slice("ABCD", 4, -1) == "");
+    assert(slice("ABCD", 0, -1) == "ABC");
+    assert(slice("ABCD", 0, -2) == "AB");
+    assert(slice("ABCD", 0, -3) == "A");
+    assert(slice("ABCD", 0, -4) == "");
+    assert(slice("ABCD", 0,  0) == "");
+    assert(slice("ABCD", 0,  1) == "A");
+    assert(slice("ABCD", 0,  2) == "AB");
+    assert(slice("ABCD", 0,  3) == "ABC");
 }
 
 rotate([70, 0, 315]) globals();

tests/horiholes.scad

@@ -0,0 +1,94 @@
+//
+// 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("blue")
+            horicylinder(r = $r, z = $z, h = 2 * eps, center = true, $fn = 360);
+
+    hole_positions()
+        color("red")
+            linear_extrude(3 * eps, center = true)
+                intersection() {
+                    difference() {
+                        square(8, center = true);
+
+                        horihole($r, $z);
+                    }
+
+                    circle($r, $fn = 360);
+                }
+}
+
+if($preview)
+    rotate(is_undef($bom) ? 0 : [70, 0, 315])
+        horiholes();
+else
+    horiholes_stl();

tests/hot_ends.scad

@@ -25,7 +25,7 @@ module hot_ends()
     layout([for(h = hot_ends) 40])
         translate([-20, 0])
             rotate(90)
-                hot_end(hot_ends[$i], 3);
+                hot_end(hot_ends[$i], 3, bowden = $i == 3);
 
 if($preview)
     hot_ends();

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();

tests/maths.scad

@@ -69,6 +69,33 @@ module maths() {
     // Test Euler
     //
     assert(euler(rotate(r)) == r, "euler() failed");
+    //
+    // Circle intersect
+    //
+    r1 = 10;
+    c1 = [50, 0, 10];
+    r2 = 20;
+    c2 = [67, 0, 0];
+    p1 = circle_intersect(c1, r1, c2, r2);
+    p2 = circle_intersect(c2, r2, c1, r1);
+
+    rotate(90) {
+        color(grey(90))
+            translate(c1) rotate([90, 0, 0]) cylinder(r = r1, h = 4 * eps, center = true);
+
+        color(grey(80))
+            translate(c2) rotate([90, 0, 0]) cylinder(r = r2, h = eps, center = true);
+
+        color("red")
+            translate(p1) rotate([90, 0, 0]) cylinder(r = 0.1, h = 6 * eps, center = true);
+
+        color("blue")
+            translate(p2) rotate([90, 0, 0]) cylinder(r = 0.1, h = 6 * eps, center = true);
+
+        translate(p1) arrow();
+
+        translate(p2) vflip() arrow();
+    }
 }
 
 rotate(45)

tests/opengrab.scad

@@ -21,11 +21,11 @@ include <../utils/core/core.scad>
 use <../vitamins/opengrab.scad>
 
 module opengrab_test() {
-    opengrab_target();
-
     rotate(45)
-        translate_z(opengrab_target_thickness())
-            opengrab();
+        opengrab_target();
+
+    translate_z(opengrab_target_thickness())
+        opengrab();
 }
 
 if($preview)

tests/pin_headers.scad

@@ -23,26 +23,56 @@ 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);
     }
 
+    for(i = [0, 1], p = [5, 2][i], j = [0 , 1]) {
+        h = [jst_ph_header, jst_xh_header][j];
+        translate([-20 * (i + 1), 0 + j * 40])
+            jst_xh_header(h, p);
+
+        translate([-20 * (i + 1), 20 + j * 40])
+            jst_xh_header(h, p, true);
+    }
+}
+
 if($preview)
     pin_headers();

tests/polyholes.scad

@@ -21,30 +21,60 @@ include <../utils/core/core.scad>
 use <../vitamins/rod.scad>
 include <../vitamins/sheets.scad>
 
-module polyholes() {
-    module positions()
-        for(i = [1 : 10]) {
-            translate([(i * i + i) / 2 + 3 * i , 8])
-                let($r = i / 2)
+module positions()
+    for(i = [1 : 10]) {
+        translate([(i * i + i) / 2 + 3 * i , 8])
+            let($r = i / 2)
+                children();
+
+        let(d = i + 0.5)
+            translate([(d * d + d) / 2 + 3 * d, 19])
+                let($r = d / 2)
                     children();
+    }
 
-            let(d = i + 0.5)
-                translate([(d * d + d) / 2 + 3 * d, 19])
-                    let($r = d / 2)
-                        children();
-        }
+module polyhole_stl() {
+    stl("polyhole");
 
-    stl_colour(pp1_colour) linear_extrude(3, center = true)
+    linear_extrude(3, center = true)
         difference() {
             square([100, 27]);
 
             positions()
                 poly_circle(r = $r);
         }
+}
 
-     positions()
+module alt_polyhole_stl() {
+    holes = [2.5, 2, 1.5];
+    n = len(holes);
+    size = [n * 10, 10, 10];
+    difference() {
+        translate([-size.x / n / 2, $preview ? 0 : -size.y / 2])
+            cube($preview ? [size.x, size.y / 2, size.z] : size);
+
+        for(i = [0 : n - 1])
+            translate([i * 10, 0])
+                if(i % 2)
+                    translate_z(size.z)
+                        poly_cylinder(r = holes[i] / 2, h = 2 * size.z, center = true, twist = i + 1);
+                else
+                    poly_cylinder(r = holes[i] / 2, h = size.z, center = false, twist = i + 1);
+    }
+}
+
+module polyholes() {
+    stl_colour(pp1_colour)
+        polyhole_stl();
+
+    positions()
         rod(d = 2 * $r, l = 8 * $r + 5);
     //
+    // Alternating polyholes
+    //
+    translate([30, -40])
+        alt_polyhole_stl();
+    //
     // Poly rings
     //
     ir = 3 / 2;
@@ -74,4 +104,11 @@ module polyholes() {
             }
 }
 
-polyholes();
+if($preview)
+    polyholes();
+else {
+    polyhole_stl();
+
+    translate([50, -20])
+        alt_polyhole_stl();
+}

tests/press_fit.scad

@@ -0,0 +1,71 @@
+//
+// 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 <../printed/press_fit.scad>
+
+module press_fits()
+{
+    thickness = 2;
+    width = 20;
+    vthickness = 4;
+
+    translate([0, width + 2])
+        difference() {
+            cube([width, width, thickness]);
+
+            for(x = [0.25, 0.75])
+                for(y = [0.25, 0.75])
+                    translate([x * width, y * width])
+                        press_fit_socket();
+        }
+
+    union() {
+        cube([width, width, thickness]);
+
+        for(x = [0.25, 0.75])
+            for(y = [0.25, 0.75])
+                translate([x * width, y * width, thickness])
+                    press_fit_peg(h = thickness);
+    }
+
+    translate([width + 2, width + 2])
+        difference() {
+            cube([width, vthickness, width]);
+
+            for(x = [0.25, 0.75])
+                for(y = [0.25, 0.75])
+                    translate([x, 0, y] * width)
+                        rotate([90, 0, 0])
+                            press_fit_socket();
+        }
+
+    translate([width + 2, 0])
+        union() {
+            cube([width, width, thickness]);
+
+            for(x = [0.25, 0.75])
+                for(y = [0.25, 0.75])
+                    translate([x * width, y * width, thickness])
+                        press_fit_peg(h = vthickness, horizontal = true);
+        }
+
+}
+
+
+press_fits();

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);
 }
 
 

tests/rails.scad

@@ -23,6 +23,7 @@ use <../utils/layout.scad>
 use <../vitamins/nut.scad>
 
 sheet = 3;
+pos = 1; //[-1 : 0.1 : 1]
 
 module rails()
     layout([for(l = rails) carriage_width(rail_carriage(l))], 20)
@@ -33,7 +34,7 @@ module rails()
             nut = screw_nut(screw);
             washer = screw_washer(screw);
 
-            rail_assembly(rail, length, rail_travel(rail, length) / 2, $i<2 ? grey(20) : "green", $i<2 ? grey(20) : "red");
+            rail_assembly(rail, length, pos * 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));
 

tests/ribbon_clamp.scad

@@ -16,20 +16,22 @@
 // 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>
+include <../core.scad>
 use <../printed/ribbon_clamp.scad>
 use <../vitamins/wire.scad>
 
-ways = 20;
+ways = [8, 20];
+screws = [M2_dome_screw, M3_cap_screw];
 
 module ribbon_clamps()
-    translate([ribbon_clamp_length(ways) / 2, 0])
-        if($preview) {
-            ribbon_clamp_fastened_assembly(ways, 3);
+    for(i = [0 : len(screws) - 1])
+        translate([ribbon_clamp_length(ways[i]) / 2, i * 30])
+            if($preview) {
+                ribbon_clamp_fastened_assembly(ways[i], 3, screws[i]);
 
-            ribbon_cable(ways, 100);
-        }
-        else
-            ribbon_clamp(ways);
+                ribbon_cable(ways[i], 100);
+            }
+            else
+                ribbon_clamp(ways[i], screws[i]);
 
 ribbon_clamps();

tests/rounded_rectangle.scad

@@ -25,6 +25,12 @@ module rounded_rectangles() {
 
     translate([40, 0])
         rounded_rectangle([30, 20, 10], 3);
+
+    translate([80, 0])
+        rounded_rectangle_xz([30, 20, 10], 3);
+
+    translate([120, 0])
+        rounded_rectangle_yz([30, 20, 10], 3);
 }
 
 rounded_rectangles();

tests/rounded_right_triangle.scad

@@ -0,0 +1,31 @@
+//
+// NopSCADlib Copyright Chris Palmer 2018
+// 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 <../global_defs.scad>
+use <../utils/rounded_right_triangle.scad>
+
+
+module rounded_right_triangles() {
+    rounded_right_triangle(10, 20, 5, 0.5);
+
+    translate([20, 0])
+        rounded_right_triangle(10, 20, 5, 0.5, offset = true);
+}
+
+rounded_right_triangles();

tests/screws.scad

@@ -18,20 +18,46 @@
 //
 include <../core.scad>
 
-module screws()
-for(y = [0 : len(screw_lists) -1])
-    for(x = [0 : len(screw_lists[y]) -1]) {
-        screw = screw_lists[y][x];
-        if(screw) {
-             length = screw_head_type(screw) == hs_grub ? 6
-                    : screw_radius(screw) <= 1.5 ? 10
-                    : screw_max_thread(screw) ? screw_longer_than(screw_max_thread(screw) + 5)
-                    : 30;
-            translate([x * 20, y * 20])
-                screw(screw, length);
-        }
+module polysink_stl() {
+    stl("polysink");
+
+    cs_screws = [for(list = screw_lists, screw = list) if(screw_head_type(screw) == hs_cs_cap) screw];
+    n = len(cs_screws);
+    size = [n * 20, 20, 10];
+    difference() {
+        translate([-size.x / n / 2, $preview ? 0 : -size.y / 2])
+            cube($preview ? [size.x, size.y / 2, size.z] : size);
+
+        for(i = [0 : n - 1])
+            let(s = cs_screws[i])
+                translate([i * 20, 0]) {
+                    translate_z(size.z)
+                        screw_polysink(s, 2 * size.z + 1);
+
+                    screw_polysink(s, 2 * size.z + 1, alt = true);
+                }
     }
+}
+
+module screws() {
+    for(y = [0 : len(screw_lists) -1])
+        for(x = [0 : len(screw_lists[y]) -1]) {
+            screw = screw_lists[y][x];
+            if(screw) {
+                 length = screw_head_type(screw) == hs_grub ? 6
+                        : screw_radius(screw) <= 1.5 ? 10
+                        : screw_max_thread(screw) ? screw_longer_than(screw_max_thread(screw) + 5)
+                        : 30;
+                translate([x * 20, y * 20])
+                    screw(screw, length);
+            }
+        }
+        translate([80, 20])
+            polysink_stl();
+}
 
 if($preview)
     let($show_threads = true)
         screws();
+else
+    polysink_stl();

tests/shaft_couplings.scad

@@ -0,0 +1,30 @@
+//
+// NopSCADlib Copyright Chris Palmer 2018
+// 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>
+include <../vitamins/shaft_couplings.scad>
+
+use <../utils/layout.scad>
+
+module shaft_couplings()
+    layout([for(s = shaft_couplings) sc_diameter(s)],5)
+        shaft_coupling(shaft_couplings[$i]);
+
+if($preview)
+    shaft_couplings();
+

tests/stepper_motors.scad

@@ -22,12 +22,12 @@ include <../vitamins/stepper_motors.scad>
 use <../utils/layout.scad>
 
 module stepper_motors()
-    layout([for(s = stepper_motors) NEMA_width(s)], 5) {
+    layout([for(s = stepper_motors) NEMA_width(s)], 5) let(m = stepper_motors[$i]) {
         rotate(180)
-            NEMA(stepper_motors[$i]);
+            NEMA(m, 0, m == NEMA17M || m == NEMA17M8);
 
         translate_z(4)
-            NEMA_screws(stepper_motors[$i], M3_pan_screw, n = $i, earth = $i > 4 ? undef : $i - 1);
+            NEMA_screws(m, M3_pan_screw, n = $i, earth = $i > 4 ? undef : $i - 1);
     }
 
 if($preview)

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);
                 }
             }
 }

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();

tests/tubings.scad

@@ -22,7 +22,7 @@ use <../utils/layout.scad>
 include <../vitamins/tubings.scad>
 
 module tubings()
-    layout([for(t = tubings) tubing_od(t)], 10)
+    layout([for(t = tubings) tubing_od(t)], 8)
         tubing(tubings[$i]);
 
 if($preview)

utils/catenary.scad

@@ -0,0 +1,52 @@
+//
+// 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/>.
+//
+
+//
+//! Catenary curve to model hanging wires, etc.
+//!
+//! Although the equation of the curve is simply ```y = a cosh(x / a)``` there is no explicit formula to calculate the constant ```a``` or the range of ```x``` given the
+//! length of the cable and the end point coordinates. See <https://en.wikipedia.org/wiki/Catenary#Determining_parameters>. The Newton-Raphson method is used to find
+//! ```a``` numerically, see <https://en.wikipedia.org/wiki/Newton%27s_method>.
+//!
+//! The coordinates of the lowest point on the curve can be retrieved by calling ```catenary_points()``` with ```steps``` equal to zero.
+//
+include <core/core.scad>
+use <maths.scad>
+
+function catenary(t, a) = let(u = argsinh(t)) a * [u, cosh(u)]; //! Parametric catenary function linear along the length of the curve.
+function catenary_s(d, a) = 2 * a * sinh(d / a); //! Length of a symmetric catenary with width ```2d```.
+function catenary_ds_by_da(d, a) = 2 * sinh(d / a) - 2 * d / a * cosh(d / a); //! First derivative of the length with respect to ```a```.
+
+function catenary_find_a(d, l, a = 1, best_e = inf, best_a = 1) =  //! Find the catenary constant ```a```, given half the horizontal span and the length.
+     assert(l > 2 * d, "Not long enough to span the gap") assert(d) let(error = abs(catenary_s(d, a) - l))
+     error >= best_e && error < 0.0001 ? best_a
+                                       : catenary_find_a(d, l, max(a - (catenary_s(d, a) - l) / catenary_ds_by_da(d, a), d / argsinh(1e99)), error, a);
+
+function catenary_points(l, x, y, steps = 100) = //! Returns a list of 2D points on the curve that goes from the origin to ```(x,y)``` and has length ```l```.
+    let(
+        d = x / 2,
+        a = catenary_find_a(d, sqrt(sqr(l) - sqr(y))),   // Find a to get the correct length
+        offset = argsinh(y / catenary_s(d, a)),
+        t0 = sinh(-d / a + offset),
+        t1 = sinh( d / a + offset),
+        h = a * cosh(-d / a + offset) - a,
+        lowest = offset > d / a ? [0, 0] : offset < -d / a ? [x, y] : [d - offset * a, -h],
+        p0 = catenary(t0, a)
+    )
+    steps ? [for(t = [t0 : (t1 - t0) / steps : t1]) catenary(t, a) - p0] : lowest;

utils/core/core.scad

@@ -18,7 +18,7 @@
 //
 
 //
-// Include this file to use the miniumum library
+// Include this file to use the minimum library
 //
 include <../../global_defs.scad>
 //

utils/core/global.scad

@@ -31,16 +31,34 @@ 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
 function r2sides4n(r) = floor((r2sides(r) + 3) / 4) * 4;                            //! Round up the number of sides to a multiple of 4 to ensure points land on all axes
+function limit(x, min, max) = max(min(x, max), min);                                //! Force x in range min <= x <= max
 
 module translate_z(z) translate([0, 0, z]) children();                              //! Shortcut for Z only translations
-module vflip() rotate([180, 0, 0]) children();                                      //! Invert children by doing a 180&deg; flip around the X axis
-module hflip() rotate([0, 180, 0]) children();                                      //! Invert children by doing a 180&deg; flip around the Y axis
+module vflip(flip=true) rotate([flip ? 180 : 0, 0, 0]) children();                  //! Invert children by doing a 180&deg; flip around the X axis
+module hflip(flip=true) rotate([0, flip ? 180: 0, 0]) children();                   //! Invert children by doing a 180&deg; flip around the Y axis
 module ellipse(xr, yr) scale([1, yr / xr]) circle4n(xr);                            //! Draw an ellipse
 
+function slice_str(str, start, end, s ="") = start >= end ? s : slice_str(str, start + 1, end, str(s, str[start])); // Helper for slice()
+
+function slice(list, start = 0, end = undef) = let( //! Slice a list or string with Python type semantics
+        len = len(list),
+        start = limit(start < 0 ? len + start : start, 0, len),
+        end   = is_undef(end) ? len : limit(end   < 0 ? len + end : end, 0, len)
+    ) is_string(list) ? slice_str(list, start, end) : [for(i = [start : 1 : end - 1]) list[i]];
+
+
+module render_if(render = true, convexity = 2)      //! Renders an object if ```render``` is true, otherwise leaves it unrendered
+    if (render)
+        render(convexity = convexity)
+            children();
+    else
+        children();
+
 module extrude_if(h, center = true)                 //! Extrudes 2D object to 3D when ```h``` is nonzero, otherwise leaves it 2D
     if(h)
         linear_extrude(h, center = center, convexity = 2) // 3D