pulley groove shape for O-ring belt

Don't know of any rule here. I used a cutoff blade the same width as the dameter of the "O" ring on a similar project. Then, I rounded the end of the blade to a 1/2 circle to match the "O" ring. After cutting the groove, I took a file and knocked off the sharp edges at the top of the cut so it wouldn't wear the ring out.

Karl

Vee shape is used for round section belts.

Paul Cordell, Nth. Qld. Australia.