VPI bearing oil/grease?

All,

Remember, that in the case of inverted bearings ... well, they're upside down.

It's been a long, long time (20+ years) since I've had one in my posession, and the issue of lubrication didn't come up.

Typically, inverted bearings have some sort of jeweled thrust bearing which doesn't require lube. As far as the side walls are concerned (in general), the oil needs to be viscuous enough to not seep out the bottom.

Unless someone has an innovative means of controlling the flow of the lube out the bottom of an inverted bearing, it appears to me that it would mandate a very thick oil, which in turn would mandate loose tolerances.

I'd love to hear more about this ...

Cheers,
Thom @ Galibier

Being an inverted bearing, how would it work if a pool of light oil were deposited in the bearing such that when the shaft was inserted the oil would work its way up the and out of the top of the bearing. A small felt concentric ring around the bearing would absorb any excess oil and keep the top of the bearing lubricated. The shaft itself would spin in a very thin pool of oil. It wouldn't take much oil to do the job.

I'm looking at an early TNT bearing as I write this. It might work though there would be some "settling time" involved to get the shaft all the way down to the point where the ball bearing is in contact with the thrust plate.

Any thoughts (as I build my table)?

Too much oil= soft muddy sound. The bearing will keep itself lubricated with the proper oil/grease. Simply re-apply occasionally.

I agree if it's thick oil or grease. But would light oil be a different story?

Bpoletti, the correct amount of oil will stay in the well, and not work it's way out of the well. No need for your "oil trap". A tip:

A few years ago, after cleaning and relubing my TNT bearing, I was dismayed at what initially seemed like boring, unexciting sound; or as some would say, no PRAT. Turned out that I had put too much oil in the well. The excess oil had accumulated around the top of the bearing well's circular top plate, and was making contact with the bottom of the platter spindle's circular bottom plate. As the platter turned, the excess oil was putting drag on it. The sonic effect was not subtle. Beware of too much oil (or grease).