Even if the wheels and rotor are perfectly balanced, all single-phase motors
vibrate torsionally. The source of the vibration is the counter-rotating
magnetic fields in the stator reacting with the rotor.
The only remedy is adding mass to the motor or motor mount. That's why
quality tool grinders have very heavy motors/mounts or use 3-phase motors.
For standard motors such as used in a A/C system blower, fans, etc.,a rubber
ring mount is often used to minimize noise and vibration transmission to the
housing.

Randy


"Catherine Jo Morgan" wrote in message
...
I have a woodworking friend who's bought a good grinder for sharpening
turning tools. She's mounted it on a regular metal post-style grinder
base,
but it vibrates a lot. Is there a better base that would minimize this?
She
has a wheel balancing kit but believes that it's the whole base that's
vibrating, not just the wheels.

Advice will be much appreciated.