Quote Originally Posted by Ger21 View Post

You said the motors are very hot? What are the motor specs, and what do you have the drive current set at?
My thoughts exactly. I've machined lots of parts often taking an hour or more and motors are never boiling hot. Warm to the touch is the hottest they get. Try turning the current down.
My understanding is that voltage is doing the work and turning down the current will help the other parts of the chain such as drivers and psi. If they are browning out under the load that is easily on the list of lost steps suspects.