I'm on the design path again, this time to build a plasma torch height controller for Mach3.

I'm going to start with letting Mach do the Z movements so my THC will simply monitor the torch volts and send the up/down signals to Machs input pins.

I've heard a certain manufacturer of a THC say Machs built in THC was too slow (???? no more details). His model fully controls the Z motor, leaving Mach to just do the XY moves during the cut.

Does anyone have any actual experience with one verses the other. What shortcomings would a THC have when it used Mach to do the Z moves. Has anyone came across this way being too slow as just mentioned.

I know Machs THC does not have acceleration / deceleration on the Z moves, and this can limit the speed at which a stepper can operate. Try to make a stepper go a certain speed instantaniously and it stalls / loses steps. Would the closed loop of a servo motor help in this regard because it can catch up to the steps commanded.

Cheers,

Keith.