pic: Poly-carbonate 2 Speed Gearbox

[jkelleyrtp]

Very nice, I've been researching good plastics for gearboxes and found that acetal and thick polycarb will work fine, but polycarb does have more flex in it. I'd recommend some sort of bracing/stand for the cims to hold them in place during load (as said above).

Also, 254 has made a plastic-based gearbox and made their mounting frames out of acetal.

[asid61]

If you could do a stress test on the holes compared to the WCP gearbox plates, that would be interesting to see.

[Cory]

Originally Posted by jkelleyrtp

Also, 254 has made a plastic-based gearbox and made their mounting frames out of acetal.

It wasn't worth it though and I'm pretty sure the solid delrin plate was just about as heavy as a pocketed aluminum plate...and substantially less rigid.

[kiettyyyy]

Originally Posted by Cory

It wasn't worth it though and I'm pretty sure the solid delrin plate was just about as heavy as a pocketed aluminum plate...and substantially less rigid.

On top of that, I recall having issues with being unable to draw heat out of the CIM motors since we used delrin plate.

We did a test with the same gearbox under the same load using pocketed aluminum plate. It resulted in having a cooler motor over the same testing duration.