Broken Lead Nut?

[Dave C]

Keep having fun Jonesy, that's what hobby machining is all about

[J Tiers]

Bronze is the normal favourite but brass will do. The original CI was not so bad and often used as it is a good wearing match with a steel screw. There is a school of thought that the nut should be a sacrificial wearing element so as not to wear the screw which would introduce dimensional errors if worn unevenly whereas a worn nut only introduces backlash. Hence brass may be the best option. (make 2 while you are at it)
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There are endless arguments about the material issue. Some say bronze is good as it will not wear the screw (probably depends on the type of bronze). Some say bronze is bad since it can embed grit and turn into a lap.

A good place to say "we report, you decide".

[Baz]

Great to get the bigger lathe running. I wondered about the clutch on your RandA. I've not seen the Portass Model S version with the RandA back gear so may be an owner modification. I strongly recommend you send a photo to Tony at Lathes.co.uk. (he takes a long time to acknowledge being busy with queries but will respond to new info like this)

[Jonesy]

Great to get the bigger lathe running. I wondered about the clutch on your RandA. I've not seen the Portass Model S version with the RandA back gear so may be an owner modification. I strongly recommend you send a photo to Tony at Lathes.co.uk. (he takes a long time to acknowledge being busy with queries but will respond to new info like this)

This is the only identical model to my RandA on the site....badged as ALTONA

http://www.lathes.co.uk/portass-s/img4.jpg