CNC Update
I’ve been busy with my CNC milling machine for watch repairs, and anything flat (minute recorder springs, setting lever springs, etc.) is no problem at all.
The final frontier are of course wheels and pinions. The fourth axis motor that came with the milling machine wasn’t very accurate, so I had to modify it in order to be usable for watch parts.
A good indicator how small you can machine is making a small pinion. Mine measures 2.5mm across, and has 18 teeth, so that’s not bad for a start.
The main problem was getting a perfectly round base for the pinion, and I achieved that by milling down the round stock in the fourth axis itself, so basically using it as a lathe. The pinion end and the shaft that you can see where milled down (that’s why they aren’t that smooth), and they would get finished off in the lathe if this was a real-world part. At the moment, I’m testing the limits of my CNC milling machine, so it’s good to show what finishes you get straight out of the machine.