Not CNC, but manual mill… Last year I bought a mill that has a heavy head with no power Z feed. I was making a power feed for the head when Google announced that they were moving up the Google+ use-by date from August to April, so my Z feed project went on standby. A few days ago I started playing with that project again. Today I ran the head up and down under power for the first time.
I still have to do the electronics and put a switch on the front of the mill to control it, but that’s the easy part. Mostly it’s ordering the right momentary-contact switch and waiting for it to arrive!