Merge branch 'jeroenrnl-SC_flex'

Added the possibility for shaft couplings to be flexible and added a 6x8
example of such a coupling.

CHANGELOG.md

@@ -3,6 +3,19 @@
 This changelog is generated by `changelog.py` using manually added semantic version tags to classify commits as breaking changes, additions or fixes.
 
 
+### [v20.12.0](https://github.com/nophead/NopSCADlib/releases/tag/v20.12.0 "show release") Additions [...](https://github.com/nophead/NopSCADlib/compare/v20.11.0...v20.12.0 "diff with v20.11.0")
+*   2022-09-27 [`c9ac393`](https://github.com/nophead/NopSCADlib/commit/c9ac393c0c7b025b3e6ad9e1030d1b13f8b879c3 "show commit") [C.](# "Chris") Printed corner blocks now have a `short_insert` option.
+
+*   2022-09-27 [`208334a`](https://github.com/nophead/NopSCADlib/commit/208334a585ed0605bf7dbaab1050c060aa15edb7 "show commit") [C.](# "Chris") Printed box now has a short insert option.
+
+*   2022-09-27 [`3a17b89`](https://github.com/nophead/NopSCADlib/commit/3a17b89d5ceb69834b23ff6bc46523f2dfb15f99 "show commit") [C.](# "Chris") Added short inserts and M5 inserts.
+`screw_insert()` now takes a short flag.
+`screw_length()` can now be passed an insert object.
+
+*   2022-09-25 [`0f36c02`](https://github.com/nophead/NopSCADlib/commit/0f36c02b5e34b0b45d258ff8e6ed4536f0601d92 "show commit") [C.](# "Chris") Added `layer_height0` global variable and updated `round_to_layer()` to handle it.
+
+ * Moved functions from `global_defs.scad` to `global.scad` so they get documented.
+
 ### [v20.11.0](https://github.com/nophead/NopSCADlib/releases/tag/v20.11.0 "show release") Additions [...](https://github.com/nophead/NopSCADlib/compare/v20.10.3...v20.11.0 "diff with v20.10.3")
 *   2022-08-30 [`c1e4625`](https://github.com/nophead/NopSCADlib/commit/c1e4625382646faf6a00e78ac01e495a88169b35 "show commit") [C.](# "Chris") Replaced generic chips with SOIC8.
 Updated images and readme.

readme.md

@@ -3481,6 +3481,7 @@ Shaft couplings
 | `sc_diameter(type)` | Coupling outer diameter |
 | `sc_diameter1(type)` | Diameter of smaller shaft |
 | `sc_diameter2(type)` | Diameter of larger shaft |
+| `sc_flexible(type)` | Flexible coupling |
 | `sc_length(type)` | Coupling length |
 
 ### Modules
@@ -3494,6 +3495,7 @@ Shaft couplings
 | Qty | Module call | BOM entry |
 | ---:|:--- |:---|
 |   1 | `shaft_coupling(SC_5x8_rigid)` |  Shaft coupling SC_5x8_rigid |
+|   1 | `shaft_coupling(SC_6x8_flex)` |  Shaft coupling SC_6x8_flex |
 
 
 <a href="#top">Top</a>

vitamins/shaft_coupling.scad

@@ -26,6 +26,7 @@ function sc_length(type)       = type[1]; //! Coupling length
 function sc_diameter(type)     = type[2]; //! Coupling outer diameter
 function sc_diameter1(type)    = type[3]; //! Diameter of smaller shaft
 function sc_diameter2(type)    = type[4]; //! Diameter of larger shaft
+function sc_flexible(type)     = type[5]; //! Flexible coupling
 
 module shaft_coupling(type, colour = "silver") { //! Draw the shaft coupling
     vitamin(str("shaft_coupling(", type[0], "): Shaft coupling ", type[0]));
@@ -34,6 +35,7 @@ module shaft_coupling(type, colour = "silver") { //! Draw the shaft coupling
     radius = sc_diameter(type) / 2;
     r1 = sc_diameter1(type) / 2;
     r2 = sc_diameter2(type) / 2;
+    flexible = is_undef(sc_flexible(type)) ? false : sc_flexible(type);
 
     grub_length = 3;
     module grub_screw_positions() {
@@ -54,6 +56,11 @@ module shaft_coupling(type, colour = "silver") { //! Draw the shaft coupling
 
                 tube(radius, r2, length / 2, false);
             }
+            if (flexible) {
+                linear_extrude(length/3, center=true, convexity = 20, twist = -5 * 360)
+                    translate([r1,0,0])
+                       square(radius-r1,1); 
+            }
             grub_screw_positions()
                 rotate([180, 0, 0])
                     cylinder(r = screw_radius(M3_grub_screw), h = 5);

vitamins/shaft_couplings.scad

@@ -21,9 +21,9 @@
 //! Shaft couplings
 //
 
-//                                   L   D        d1   d2
-SC_5x8_rigid  = [ "SC_5x8_rigid",    25, 12.5,    5,   8 ];
-
-shaft_couplings = [SC_5x8_rigid];
+//                                   L   D        d1   d2 flex?
+SC_5x8_rigid  = [ "SC_5x8_rigid",    25, 12.5,    5,   8, false ];
+SC_6x8_flex   = [ "SC_6x8_flex",     25, 19,      6,   8, true ];
+shaft_couplings = [SC_5x8_rigid, SC_6x8_flex];
 
 use <shaft_coupling.scad>