[Jay H 237]

Have you considered using polycarbonate instead of a metal plate? It's similar to plexiglass but much stronger and won't shatter. You could then use regular screws to mount the motor to the polycarbonate and it would still be isolated. It can be drilled and cut easily. I'm not sure what your planning on doing with the motor but polycarbonate or another noncondutive composite material might be your answer.

Also is there a posibility that whatever you attach to the motor shaft could cause a short to ground somewhere? What I mean is if there's a metal sprocket with a metal chain going to another sprocket on a shaft it could also ground out somewhere where that shaft attaches to the frame for instance.