Dyna Mechtronics built some great small CNC milling machines in the 1990's. You can often find good deals on them today but the old control they used is very dated and many times they are not working.
After converting a Dyna 2400 mill a few years ago we put together a kit of parts to make it easy for you do the same conversion. This same kit can be used for the 2200, 2400 and 2800. We have also compiled a lot of information on the subject which you can find in the documentation section here.
The kit includes:
G540 w/EZ-G540 and heatsink
Ethernet SmoothStepper, Ethernet cable, 2- LPH26 toDB25, DB25 M-M adapter, 5V power supply
2 24V relays
12" panel mount Ethernet cable
Mach3 or Mach4 License (optional)