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Variable speed pulley Rockwell 11" lathe - is this too much run out?

Dan_the_Chemist

Aluminum
Joined
Feb 14, 2016
I am repairing a Rockwell 11" lathe that suffered years of neglect in an unheated space. I have disassembled it to access the variable speed pulley - as shown. The central bi-cone has a bushing that looks like a composite of bronze and some black material... or very oil soaked bronze sinter.

The shaft is still round and parallel 1.717 +/- 0.002 The bushing is 1.732 +/- 0.024 The photo shows some small chips out of the rim, and that the inside face is not smooth. It wobbles quite a bit by hand as shown in the 20 second vid.

I suspect this is WAY too much run out, but I've never examined a working variable speed pulley, so I want to confirm it.

The thing that surprises me is that it went from smooth running to light rumbling for 12 hours of use, and it began heavy rumbling for 6 hours of use, and then it went "over the cliff" in just 10 minutes. I fully expected to find something that was catastrophically broken because it was so sudden. It seems like a lot of wear for just 10 - 12 hours from smooth to BLAP. Or is this one of those things that once it starts to fail it goes quicker and quicker.


Of course, the solution is simple. I'll just make a new bronze bushing using my Rockwell 11" lathe. Except that the lathe is laying in parts... oh dear. Catch 22

medium sized variable speed pulley.jpg
close up sleeve.jpg
close up bushing.jpg

...

TIA
Dan
 








 
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