Staircase Marble Machine

This is a re-work of Automata - Marble Machine by Sebastian Bolona, to make it more suitable for 3d printing.

It has the following parts:
- base
- top
- shaft
- nut (goes on the end of the shaft)
- cams (five of these needed - fit alternatively up and down on the shaft)
- lifts (five different ones, of increasing height)

The finished machine works best with 6.35mm ball bearings.

The parts are designed with 0.2mm clearances, but you may need to file them a bit depending on th