It works. Very well.
Here is what a 20+ year old milling machine can do, with 3rd party software. It was originally designed to be a hobby/educational milling machine, for milling balsa wood into model cars/co2 cartridge powered cars.
It also drilled all 369 holes for me. PCB was done with a 45 degree general engraving bit. I zero'd the Z axis by hand knobs on the motors, moving down until the bit just barely started to scratch some duct tape I had holding the copper clad board down, the traces turned out just as big if not smaller than my shitty acid-etch attempt.
Plus internets to whoever can guess the mill manufacturer/model. It is upwards of 20 years old, and 20 years ago it was $10,000.
The software I used is
Galaad, definitely recommend it. Has everything needed to control these old machines with built-in preprocessors and memory limits (toolpaths are loaded one at a time to deal with the memory limitations on this machine). It also has a PCB design/mill feature.
Comments
^Reddit
Don't forget to tin the traces or make a polyurethane solder mask. If you don't the PCB isn't going to last very long.
http://reprap.org/wiki/Generation_7_Electronics
I'm about to rage at this thing...I know the board is fine, but there's something screwy with the programmer or atmega, I can't program it and computers can no longer connect with my programmer...