That would be an F1 Ferrari plasma cutter then? :naughty:

Let's make it work hard, 1" travel per stepper rev, massive 20kg gantry.

If I've got the maths right, 3Nm would do nought to 83 mph in one second.

I know you need some degree of overkill to compensate for the losses, but a smaller, faster revving motor would seem to be a better bet.