Quote Originally Posted by vortexwizard View Post
would adding smoothing capacitor after rectifier help smooth signal and increase motor life? also would the varying/pulsating speed you mentioned possible cut down on harmonics/chatter when used on a lathe.
thanks
In general adding a capacitor helps with smoothing.
Your second point is very interesting but there is no simple answer. Sometimes adding a source of extra vibration can help kill the effects of another, like chatter. However, this is unlikely to be a general answer and in some cases it might make thing worse.
My approach would be to feed the motor as smoothly as practicable and look for chatter cures elsewhere, machine rigidity, cutting tool angles, depth of cut, speeds and feeds, work stick out or overhang etc.