This is the pulley from the lathe that I think is causing problems. When it was initially stripped down 10 years ago, there was a crack from the corner of the keyway going through to that reduced diameter section. There is an oil seal on that reduced diameter, so the edges of the crack may be very slowly scraping away the seal or the oil is just seeping through the crack. Either way it needs to be fixed as over those 10 years I think I've lost maybe 100ml of oil and as I have a lump of CI that would make a new pulley, I should do it sooner rather than later as the loss rate will only get worse. The shaft it sits on comes from the bottom of a gear box with 5 litres of oil in it, and the pulley is secured on with a nyloc nut. I liberally applied sealant around the nut so that any oil that did migrate could not sneak out around the nut
Output pulley.jpg
As you can see, the distance between the corner and the diameter is not very much at all. Reviewing my options, I'm thinking I could possibly

  • Grind the key down so that the keyway in the bore does not have to be so deep
  • Swap the current seal (suitable for a diameter 30 shaft) for one a little larger (1-1/4" or 32mm) and make the reduced diameter larger on a new pulley to suit
  • Make a new pulley from steel instead, which would better resist the tensile forces in that area
  • Sleeve the (existing?) pulley so that it has a smooth surface to run on (ie no crack running under the seal).



Combinations of all of these are probably possible. Any other ideas out there? Any of these leap out as a head and shoulders solution?

Michael
Attached Images




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