recommended oil for well tempered spindle cup

btw, the link above is for 0w20
the recommendation of the designer was for  5w20 or 5w30

There is just no need for two weights, unless you’re planning on 5000 rpm.

This is not to contradict Firebaugh. He was probably exaggerating. Or picked some numbers out of the air. By all means do go with his recommendation.

I owned a WTRP and my experience was that the stretchier the belt the heavier weight oil was optimal. When I had my original stiff belt or the mostly OEM Stanalog replacements, the then recommended 50W motor oil worked great. When George went out of business, only stretchier belts were available and 90W gear oil made them tolerable. When I was finally patient enough to make a proper string drive, then 5W mineral oil helped the string not to slip but didn't raise the bearing noise level.

Not sure of the current state of belt availability for WT tables, so YMMV. If Bill has OEM belts as replacements, then you should definitely follow his oil recommendation.

David

I am sure your direct experience is more cogent than my guesswork, but one might think that with a stretchy belt, higher viscosity would engender more belt stretching which might lead to more speed irregularity.  Just thinking out loud. Anyway, my bottom line contention is it doesn't make much difference what lubricant you use.  If I recall my friend's WTRP, the "bearing" actually consisted of some white protrusions in the well, maybe one or two rounded hemispherical white plastic mounds, which contacted the spindle when the belt pulled the platter toward the motor.  Very unconventional to begin with.

April Fools!

All of you.

I use Virgin Olive Oil. Just a drop so there is only a thin film of lubricant, more than a drop creates resistance. I also have taken the cup and the spindle to a triboligist and had a molybdenum coating treatment so that the rod end bearing can be run dry when at my home in the high desert in Oregon.