So many good replies here, lots of good information. I wonder how we ever made is through life before these forums existed internet ha ha. Im thinking that the 3 phase/VFD Will solve it. But that doesnt mean it was the motor, had the old motor come back here too, put it on my machine, and cuts just fine. (And while these arent Baldor motors, they are still pretty decent motors from Taiwan) What I believe is since the single phase motors are just not quite as smooth as the 3 phase w/VFD (Although in most cases smooth enough on this model for a good finish) and since its on the stud floor, its not absorbing that vibration, it might even be magnifying it. And the 3 phase will have less vibration, so not as critical what kind of floor its on, so hopefully that takes care of it.