FYI I’ve work it out with dynamics. First gear is set as a collider and keyframed to rotate.Second gear is set as a rigid body, then connected to a base with a connector (hinge). But what I was missing is that both dynamics tags should have their collision shape set to MOVING MESH.
Thanks Shawn, no I didn’t know all that. I’m fairly new to C4D all together so I haven’t played with Xpresso much. Sounds pretty straight forward with the multiply node, I’ll have it a go.