Algodoo

Thx! How did u do it?

1. Replace tracer with circle.
2. circle._surface = "";
3. circle.postStep := (e)=>{_surface = _surface + pos + ","};
4. Start scene let motor move 1 revolution.
5. Copy circle, paste into notepad.
6. Make any small polygon.
7. Copy polygon, paste into new notepad.
8. Copy notepad.circle._surface value, paste into notepad.polygon.surfaces.
9. Copy all notepad.polygon.
10. Paste notepad.polygon into Algodoo.
11. Make a box larger than housing cutout.
12. Subtract housing cutout from box.

OHHH so you actually make the inside, and then use it to cut the outside. Very neat!