PolyBot Rod Sphere Cap

This design reaches into the waaayyy back machine. I have need to put balls on the ends of rods.

This thing is an improvement over the original design I did a while ago. The difference is the shaft has an internal taper, which increases the friction fit the further you push the rod into the fitting.

There is also an opening at the top of the sphere. The intention here is that you can use the opening to put epoxy into the cavity, to give the shaft a bit more bite beyond the friction fi