"Ned Simmons" wrote in message
...
In article ,
says...
Grant (or any one else),

If you have a chance and feel so inclined would you take a look at this
site:

http://member.newsguy.com/~mphenry/s...&_bearings.htm

I've uploaded some pics there along with a brief description of what has
been done and observed so far. It's a bit rambling and not especially
well
organized.

I'm especially interested to find out if the spindle bearings appear to
be
the proper type, or at least the one that I could get a picture of. I
found
an old 1985 Fafnir catalog that provides some info on the 2MM9105WICRDUM
bearings that you referred to in an earlier post and these look similar
but
I'm not sure about the reddish brown part of the bearing. Is that the
(CR)
composition cage, which is apparently non-metallic?

It looks like the retainer to me.

Thanks - for some odd reason it looked like an O-ring at first, which made
no sense at all.

If this were my spindle and I didn't need to have it
running tomorrow, this is what I'd do. Disassemble it, take
careful note of how it's built and make sure you understand
why. Take lots of photos in case you need to ask questions.
Make sure to keep the paired bearings together thru the
whole process.

Wash the bearings thoroughly, inspect them carefully under
a stereo microscope for any obvious damage or wear to the
balls and races. Assuming they aren't obviously NFG, give
them a final rinse in clean acetone and regrease.

Reassemble the spindle. If they're identical, switch the
two pairs of bearings, back pair to the nose. The bearings
at the nose likely take more abuse than the back pair and
have more effect on the runout.

Worst case, the spindle will be no better than when you
started, but you'll have learned something and had a
practice run rebuilding the thing without jeopardizing an
expensive set of new bearings. If you've lived a clean life
and help old ladies cross the street, the runout may be
improved.

That sounds like a reasonable approach. A knowledgeable friend is willing
to stop by and check it (and my grinding technique) out in a week or two,
so I'll probably wait until then to dig into the spindle. It's been
suggested to me that the runout characteristics (max and min just about
exactly 180° apart) indicate that the spindle may be slightly bent. If
that's true, working on the bearings probably won't help, but then dressing
the wheel sufficiently should eliminate any eccentricity that would cause
scalloping.

Someone else though that the table rack or gear may have some sort of
problem that is contributing to or causing the scalloping. I'll check that
out tomorrow night after work. At least the rack would (probably) be
cheaper than new bearings, but it won't do any thing to reduce the run out.