Compact 3CIM Single Speed Gearbox Review

[asid61]

Originally Posted by gc_coxen

1. We were trying to maximize use of COTS, so those are AndyMark AMS Cluster Hex Shaft (am-0302).
2. Is there any reason to add a plastic cover? Seems like unnecessary extra weight.
3. I came back part way through the render queue and regretted using the powdercoat texture, looks awful. Oh well.
4. There is only one bolt that uses a nut, the rest of the bolts go directly into the cims. I thought I'd be better off with a locknut vs. a tapped hole.
5. We currently have the parts for a single speed configuration, although I think a dogshifter would be possible. As long as the edge of the CIM doesn't interfere with the standoffs holding the pancake piston.

Sounds fair! Good reasoning for using the shorter shafts, sounds like you'll save a lot of money/time if you make this.
I assumed you made the pates so large (the size of the gears OD) so that you could protect it or something. If you're not interested in using a cover, you can bring the edges of your gearbox to the bearings rather than the OD of the gears, unless it's an aesthetic choice.

EDIT: 16ft/s free speed isn't too fast IMO, especially if you run 6 CIMs. On a 4 CIM drive your acceleration suffers, but 6 CIMs will make the difference.