VFD for return to 3ph?

[f350ca]

(10-23-2013, 06:57 AM)stevec Wrote: Sunset, just as an aside, does the mill now powered with a 1 ph motor perform as well as it did with the original 3 ph one.?
By perform I mean smooth cutting and good finish?
Of course it's possible you, like I, probably never ran it under 3ph power.

I've heard this mentioned before but have a hard time imagining you can see the difference in finish.
If its a 4 pole motor you get 4 smooth sinusoidal pulls during each revolution on single phase vs 12 on 3 phase. Its not a pulse its a building and falling magnetic field. if the motor was at stall speed maybe you'd feel the rising and falling torque but at running speed the rotating inertia of the armature and associated load would have to mask the source. When your driving down the highway at cruising speed some new engines cut out cylinders for economy, does the ride get jerky?
I thought the advantage of 3 phase motors was physical size, instant reversing and no effect when numerous starts were required.