Thanks for the comment.
I made the above spiral scene by cloning one tooth onto a log spiral, then using the pen tool to join start to end. The hard part was where the start on one cog meets the end on an adjacent cog. I made an instance of the working cog spline and flipped it 180 deg to represent a 2nd, so I could tweak the points until they fitted.
The center cog is an animated collider and the other 2 rigid bodies - so it runs on dynamics.
I only started this little quest after seeing 'impossible' gears (eg square) on YouTube, wondering if it was a con, then building them in C4D as a test. I usually check for any movement of object centers or hinge positions in attrib manager when the model is running, as proof of concept.
3 spirals.c4d