So I did some tests:
- with the Z-axis: the inner piece will always pop of the shaft after going down 2 times
- without the Z-axis, but inner piece attached: if I press it down manually, I get the depth i need
So the problem is the inner piece popping off the shaft. Should I attach it with some hot glue?
Edit: found some clues in following topic:
- Ned just pushed it into place
- Dag put some screws in it to hold them together
I think I’m going to try screws to.