Re: Balancing an RSG rotor

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Parpp807-at-aol-dot-com>

In a message dated 10/28/02 8:51:18 PM Central Standard Time,
tesla-at-pupman-dot-com writes:

Aric,

The machinist could have screwed up. Have you tried placing the disc flat on
a table and checking the measurements? Does the motor itself run free of
vibration?
You mentioned that you have the G-11 mounted to a pulley. Would you please
describe
the arrangement. John's suggestion of trying to balance the disc as you would
balance a tire sounds very good. You wrote that the electrodes are 1 1/2
brass rods.
I assume that is the length of the stud which is about right for a 1/4 inch
thick disk if you are using the heavy brass nuts.  3/8 diameter  threaded
brass is about right. Hold them to the disc with the
oversize brass nuts you can find in the McMaster catalog.. These are big
thick jobs that will really clamp down. I have the electrodes extending no
more than 3/8 inch from the nuts. A mechanical resonance situation is
possible if the studs protrude too far.

Happy day,
Ralph Zekelman

 > The disk was machined on a milling machine.  The disk and electrode holes
 >  were machined about a central hole.  I don't
 >  know the method the machinist used to fix the angle between electrode
holes.
 >
 >  The electrodes are 1 1/2" threaded brass rod, held in place with nuts,
flat
 >  washers, and lock washers.  The vibration
 >  was observed before installation of the electrodes.  I have yet to test
the
 >  rotor with the electrodes installed.
 >