Hi,
I've made a cnc controller based on an Arduino UNO for my cnc mill:
- Its not strictly an Arduino project - I've used AVR Studio 6 Assembler / VB.NET but its free, open source and uses an Arduino UNO so you might like it nevertheless...
- Uses a wireless Logitech gamepad to manually control the machine from a few steps per second up to full speed.
- Controls the VFD of a spindle motor with just 2 resistors, 1 capacitor and 1 optocoupler...
- Quite fast... >>70000 steps per second...
- Some built in commands for drilling, circles, rectangles etc. with macro editor - quite nice for simple tasks that may be done without CAM program...
More Information and sources: Estlcam: 2D / 3D CAM und CNC Steuerung...
Christian