Originally Posted by
mwood3
Ok, well i imagine it will be at least x2 the resistance(if not more) with the lapping compound method that is being discussed here...no oil...just adding lapping compound and tightening the gibs as you go...I second the opinion of letting the motors rest between cycles if it takes very long to lap it in.
As Ray says, a properly set up system doesn't need to "rest" the stepper motors. And the argument that there may be more friction is also moot because the steppers are ALWAYS running at FULL TORQUE. The motor has no idea how much friction there is until its torque requirement exceeds what the motor will produce. If it turns the screw, it will be as hot as it will get no matter the load.
Also, stepper motors are typically designed to operate with a 40*C temperature rise (which is 72*F). So if the ambient air temp is 75*, the motor will run about 150* with no problems. This is hotter than you can comfortably touch the motor. Besides, why would you design the system for anything LESS than 100% duty cycle?????
"Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away." Antoine de Saint-Exupery (1900 - 1944)