I ran it on a Via single board computer, a tiny board that sipped power and was still more than beefy enough to do real time control of 3 axis stepper motors and maintain a connection to the outside world. I cheated a bit by disabling interrupts during time critical sections and re-enabling the devices afterwards took some figuring out but overall the system was extremely reliable. I used it to cut up to 1/4" steel sheet for the windmill (it would cut up to 1" but then the kerf would be quite ugly), as well as much thinner sheet for the laminations. The latter was quite problematic because it tended to warp up towards the cutter nozzle while cutting and that would short out the arc. In the end we measured the voltage across the arc and then automatically had the nozzle back off in case of warping, which worked quite well, the resulting inaccuracies were very minor.

https://jacquesmattheij.com/dscn3995.jpg