JVN Build Tip: CIM Pinions

[JVN]

The CIM motor has 0.75" diameter protrusion on its face which is GREAT for piloting (keeping the CIM centered where you want). Relying on the (2x) 10-32 mounting screws will work, but won't result in as consistent a mounting. If you have any slop in your mounting holes the CIM could shift, resulting in a loose or tight gear mesh.

Typically, people use a 12-tooth or 14-tooth 20DP gear as a CIM pinion (see KOP transmissions).

One of my favorite tricks? Always opt for the 12t pinion. The 12t gear fits through a 0.75" hole while the 14t gear does not. This allows you to swap a CIM motor in/out without removing the pinion gear. You can have CIM motors on-hand ready to swap in.

Then again... I've never had to remove a CIM motor except to work on something else... Maybe this isn't such an expert tip after-all.

As always... good luck in 2011!

-John

Originally posted here: http://jvengineering.blogspot.com/20...m-pinions.html