Now at the Makerspace leiden we have a nice lathe. And there is usually plenty of scrap laying around. This time someone has donated some very tick aluminium pegs; one of these is just about the right amount of material.

First step is to determine the order. We want things to fit reasonably well so that nothing is wobbly (though the spring will help compensate just about anything). 

We need to make three things; a the bottom 'cup' with a recess at the bottom for the magnet. The sliding middle thing ; which essentially is also a 'cup' for the spring. And the pin that goes through the middle with a flat top.

For the middle bit - it is somewhat critical to have the outer walls parallel to the inner wall that slides along the middle pin to prevent binding. The same applies to the inner walls of the bottom cup and the threaded hole in the bottom.

So we'll do those in one session; without taking it out of the three-claw chuck.