I just revived a 1990s Millport CNC mill from a non-functioning brick to a floppy-wielding chip thrower. I detailed the troubleshooting process and PCB level repairs needed to make this DOS based servo-drive CNC shift some 1s and 0s and throw chips again.
It's always nice to see a detailed write up, a lot of cnc mill repairs end up replacing the existing control hardware but this write up was a curious take on maintaining the existing electronics, which takes more talent than replacing.
Thanks! The repair was a bit involved and drawn out, but well worth it :D