[morzh]

I refilled the ball race with new 2mm balls. The holder I came up with worked nicely. It was not a walk in the park, but unlike before, it worked within a reasonable amount of time.
The bearing became quieter.

However there is still noise and I eventually traced it to the motor. I do not intend to rebuild the motor in full; if I ever get my hands on a quieter one I will replace it.

I need to replace that mat. I think I will acquire a second felt mat, cut it to accept the center ring and be done with it.
Then the needles will go in and I will try it.