Added source code

tests/rails.scad

@@ -0,0 +1,48 @@
+//
+// 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>
+use <../utils/layout.scad>
+
+include <../vitamins/screws.scad>
+include <../vitamins/rails.scad>
+use <../vitamins/nut.scad>
+
+sheet = 3;
+
+module rails()
+    layout([for(l = rails) carriage_width(rail_carriage(l))], 25)
+        rotate(-90) {
+            rail = rails[$i];
+            length = rail == MGN15 ? 260 : 200;
+            screw = rail_screw(rail);
+            nut = screw_nut(screw);
+            washer = screw_washer(screw);
+
+            rail_assembly(rail, length, rail_travel(rail, length) / 2);
+
+            rail_screws(rail, length, sheet + nut_thickness(nut, true) + washer_thickness(washer));
+
+            rail_hole_positions(rail, length, 0)
+                translate_z(-sheet)
+                    vflip()
+                        nut_and_washer(nut, true);
+         }
+
+if($preview)
+    rails();