After 20 years or so running, the 401 bearing thread made me think I should look at mine. It was getting a bit noisy with a small scraping noise about every revolution.
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There's quite a bit of wear on the thrust plate. I can't remember the material of the white one which was an upgrade over the original so that's going in.
When I spin the shaft on the thrust plate I can see the ball grips the thrust plate so the shaft spinning on the ball was probably the scraping noise.
Rest of the bearing seems fine so looking forward to putting it all back together. Just got to find the place where it says how much oil to put in.
Well, turns out it is Delrin, a ptfe filled plastic.
You can get teflon bar or flat at those gatherings around the country between model engneers and the people selling them machinery and consumables. I dont have time for them these days.
If I were designing a thrust plate for a turntable Id use ptfe bar, made to fit.
Though I doubt it would better an original grease bearing. If I were a turntable engineer Id reverse engineer that.
As for 401 not sounding as good to me as a 301. They are made of different materials, why would two things with different metalergy sound the same?
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
I have loads of delrin rod knocking around, i use it to make replacement thrust pads for lenco bearings. The original thin nylatron material is no longer obtainable under that name, or if it is ive not found a source. it is probably available under some other name.
But delrin is readily available and turns very nicely you can get a lovely surface finish when facing the side the ball will sit on. I prefer it to the practically always ruined original pads
I don't think it has teflon in it, Paul. Here's the blurb : https://en.wikipedia.org/wiki/Polyoxymethylene
Delrin as a trade name is mentioned in the first paragraph, and in the third paragraph of 'development'.
It would need to have fluorine in the structure to be a teflon variant.
"Once you find out ... the Circumstances ; then you can go out"
Looking at the Teres manual…. The thrust pad is Delrin (I know it’s a novel concept to read instructions ). Looking at their sectional drawing I am unclear where the metal disc goes. https://www.vinylengine.com/library/teres/bearing.shtml
vinylnvalves wrote: ↑Sun Jun 25, 2023 6:43 pm
Looking at the Teres manual…. The thrust pad is Delrin (I know it’s a novel concept to read instructions ). Looking at their sectional drawing I am unclear where the metal disc goes. https://www.vinylengine.com/library/teres/bearing.shtml
I seem to have an early model before the delrin disk embedded in the brass plate. First brass plate, then delrin disk, then the combined thrust pad.
Took about 6 hours for bearing to sink home. Looking forward to tunes this evening with no scraping noises hopefully.
). Looking at their sectional drawing I am unclear where the metal disc goes. 
the Delrin thrust pad is meant to be bonded onto the metal backing plate.