Hi guys,
the beauty of the G-Rex is that you don't need break-out boards. Even though the G-Rex is the pulse generator it is also the i/o board, and the breakout board. Full 6 axis. You will need the G-rex, Mach4 or some other controller when available, and as many drives as you want up to the 6. There is a video on the mach support site showing a large milling table running under G-rex/Mach4 control and it is soooo smooth. It is also running at 300 inches per minute. This particular machine has large servos rather than steppers.
I personally am excited about Mariss's (Mr. Gecko) new un-stallable stepper solution and will probably wait for that depending on how long he projects it to take.
Mike
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