A few years ago I started learning about CNC mills. I was not interested in 3D printers because of the material limitations.
Most of the hobby CNC machines I see use an old computer with a parallel port running Mach3 software. I am good with electronics and was learning Arduino so I decided to make an easy to use CNC controller that left my computer free for other stuff.
I started with a simple setup, just a Spider controller, SD card interface and a LCD. Once I had the SD card and LCD libraries worked out I designed a controller using the Allegro A4988 stepper motor drivers but unfortunately they overheated too easily so could only deliver about 1.2A reliably. I also had some other small problems that required a PCB re-design.
The new controller now uses Toshiba TB6560AHQ motor drivers mounted on a tunnel heatsink with dual fans. I have now mounted the controller in a professional housing with an emergency stop built in.
The controller is an ATmega2560 with an ATmega8A slave processor. All the software has been written using the Arduino 1.0.6 IDE. So far I have tested it with 3 and 4 axis machines. The controller is capable of driving a 5-axis machine or the extra outputs can be slaved to the X, Y and Z axes.
The controller is now available on Indiegogo: http://igg.me/at/EasyCNC
Read more about it here:
Hackaday: https://hackaday.io/project/9159-easy-cnc-controller
RobotRebels: http://www.robotrebels.org/index.php?topic=388.0
CoolKidsRobots: http://coolkidsrobots.com/robot/easy-cnc-controller