I was playing with sprockets and chain for driving L3-G0's motors (http://L3-G0.blogspot.com - My full size Lego R2D2, video on Youtube). Having difficulty finding a sprocket supplier, I decided to print some, but I wasn't able to find an OpenSCAD type sprocket library.

This "knows" about many types of ANSI chain, Motorcycle Chain, and maybe Bicycle chain, but I've only tested with ANSI #25 roller chain because that's what L3-G0 uses.

Sizes are: #25, #35, #40, #41, #50, #60 & #80 roller chain, and 420, 425, 428, 520, 525, 530 & 630 motorcycle chain. You can comment if the other sizes work for you (& if you had to tweak the fudges).

L3-G0's complete now, so check out his blog & share with friends. Also please give a thumbs up on his video channel!

Though I included a couple .stl files, Sprockets is intended for you make your own size sprocket using OpenSCAD. It's fairly easy to do your own thing, and if you forget, there're comments in the sprockets.scad file. Skip the first steps if you've played with OpenSCAD and know how libraries behave.

1. Get OpenSCAD if you don't have it already, http://www.openscad.org/
2. Copy sprockets.scad to some folder on your machine.
3. Either use a real library location, or to KISS, just make a new document and save it in the same folder as sprockets.scad.
4. Enter something like this into your OpenSCAD script (on the left)
   `use