9-pin sprocket for bicycle chain

thingiverse

Needed a sprocket to direct-drive a bicycle chain from a stepper motor. First try, the fit is a bit rough - we'll see. Will add more details/fixes if/when it's together and working. Second version looks like it'll work well. Instructions Made this on a Cupcake CNC, basic build platform. Used Google Sketchup 8 and the DXF/STL export plugin. Recommend using 9_pin_stepper_sprocket_final.stl - that one worked. Using a raft helped keep it perfectly flat. As soon as the printing is done, insert the stepper motor shaft and level it, then hold still while it cools. This makes it fit snugly and keeps it straight so it'll actually be usable.