[Steve Compton]

opps - there it is, thanks!

Originally Posted by artdutra04

Attached is a STEP file of the sprocket I machined in the photos above. All I did was download a regular sprocket model from McMaster-Carr (they have CAD models for most of their hardware (screws, nuts, shoulder bolts, sprockets, etc) on their website), use calipers to measure the metric output "spline" of the Denso motor, draw it on the part, and extrude cut it.

To machine it was a four step process. The first thing I had to do was machine a fixture plate out of 6061 aluminum. Then I machined about 90% of the sprocket features onto the 1/2" 7075 aluminum raw material. Then I took that part out, bolted it to the fixture plate upside down, and machined the sprocket teeth into it. The last step is to use a lathe or hand file to bevel the teeth.

There is nothing in this CAD model to keep the sprocket on the shaft of the motor or to support it for cantilevered loads. In the second photo I previously posted, our solution was to machine a custom bushing out of Delrin to both support the shaft and to keep the sprocket laterally in place on the shaft.