In my last update I promised a video of a relay working so here it is

The relay used looks a little different then the ones I showed in the last update because I was having difficulty with reproducing it without fussing every time to get everything just right and moving one of the contacts that had a wire attached was influencing the system too much. Instead I put a washer on one of the shafts and moved that, this seems to me much more predictable however I still expect to keep iterating on this design so that the directions won't have to include "move until it almost touches". Also I am still experimenting with spring replacements

Here is what the piston looks like

and when its all together the version in the video looks like this

Also last update I was having trouble with magnets sticking well and indeed scuffing them up before glueing has worked much better as you would expect.

Up next will be the inclusion of a hall effect sensor component and then I believe the last component will be the commutator for the brushed DC motor, with several additional reference designs following that. So look for those updates soon!