// https://gitorious.org/ozzloy/challenge-bot
// https://github.com/waynegramlich/challenge-bot
+// use this drill jig for putting holes in a motor mount for screws
+// and motor shaft. the four tabs at the bottom are for clamping
+// the jig down.
+
mm_per_inch = 25.4;
material_width = (1/8) * mm_per_inch;