pic: WIP 3 CIM 2 Speed All Belt Cim Above Tube Gearbox

[Colin Small]

Originally Posted by asid61

For your second stage pulleys, they are constrained in rotation by the hex bore. Let's say you accidentally broach one so that the tip of the hex lines up with a groove, and the one next to it such that the flat of the hex lines up with a groove.
At this point the two pulleys do not perfectly match up in their rotations. This wouldn't be a problem, only for their mating pulleys you have the same problem- the teeth may not match up.
This means that you could face some major indexing issues that would screw up the meshes on at least 1 pulley at a time.
The way to fix that would be to use a jig to align the pulleys before broaching/machining.

Ah, I see.

Considering that there'll be three holes for joining the two sets of large pulleys, I don't see a problem with those. If I do end up having this made I'll probably use a jig for the driving pulleys.