Cnc plasma build need help plz

[JAZZCNC]

Its just very confusing that the motors turn fast when im using the protuner software

The reason is because the Protune uses the drives own built in Pulse generator and it's default Micro stepping settings. It doesn't use Mach3 at all.
The reason why you are getting such low speeds is because you are using Mach3 to provide the pulses and you have limited number of pulses available. Now because you have set the Steps Per setting so high the Max speed is drasticly low.

What you have to understand is that Steps Per is a Calculation and MUST be correct. It's not something you can play around with other wise the machine will move the wrong distance.
Provided the Numbers you gave me are correct then those settings will work and you will get more speed.

The Low voltage will reduce the speed and Torque you'll get from the motors but it will still give you much higher than the Max 750mm/min the 2000 Steps per allowed. Difficult to estimate how fast because lots of factors come into play but I'd say easily 2000-3000mm/min for starters.