Building a watchmaker's lathe countershaft

[cazboy]

I guess you all know I'm going through a big learning curve with my Rivett lathe. Speed control, type of oil to use, all kinds of stuff.

So I've decided to build a countershaft. I already have a small diameter (3/4") step cone pulley. It has a 1/4" bore. But now I need a larger diameter (3-1/2"? 4"? 5"?) step cone pulley to mount on the same shaft, and I can't seem to find one anywhere.

Has anyone here ever built a homemade countershaft? Where can I find a larger diameter step cone pulley with a 1/4" bore? I've looked all over the usual places like McMaster Carr, MSC, Enco, etc. Help guys! Thanks. I'm attaching a picture of a step cone pulley to show what I mean.

 

[Tinker Dwight]

Hi
If worst comes to worst, you have a lathe. You
can turn some sleaves in brass to adapt a larger
shaft down to 1/4 inch.
Tinker Dwight

 

[the 3rd dwarve]

Doug,

Try a more specialized shop to find your sheave. A bearing supply house will be able to get you any sheave available. You will need one that has small grooves like a size A or even smaller depending on the size of your drive belt. As an example, I use Future Bearings because they are local to me. http://www.futurebearings.com/main.htm

If you can’t find what you want turn up a custom one.

Regards,

Jeff

 

[StephanG]

As a short term solution you can make one from wood.

Use a bit of brass say 1/2 inch and add the 1/4 hole and a grub screw at one end. Press this into a bit of nice timber ( drill a slightly smaller hole first ) and then turn the groves as required. Rough up the OD of the brass a bit to help it grip. Perhaps file some flats on it.

This will get you going and then you can make a nicer pulley from metal at your leisure.

 

[gvasale]

I don't know why you want a larger cone pulley. I think one that mirrors the one you have would do. Another thought if you are determined to get higher speed would be to use another intermediate shaft. Plus, I wouldn't expect to find a pulley of the quality your looking for in any non clock/watch supply stream. Used at a Mart, yes. Otherwise you might have to make one.

 

[cazboy]

Thanks guys. The pulley I already have (the one with the 1/4" bore) is a small one, it's one of the ones that go on the end of the shaft of a lathe motor. It has three steps. So maybe I don't need another step pulley after all - maybe what I need is a single larger-diameter pulley!