In Need Of A New Lead Screw Nut

[malar]

I have an old SB lathe and the lead screw half nut is worn.
I made one years ago out of mild steel. My concern is will this wear the lead screw if I use it?
Or worse gall. I didn't have any bronze then and have only brass now.
Do I go with the steel and not worry or order some bronze?
I can't up and buy one. It's a 7/8" X 8 TPI acme and none are to be found.

 

[David VanNorman]

I think I would buy enough bronze to make a new one. The steel one will wear your lead screw.

 

[Dave Paine]

Try contacting Miller Fabrication to see if they have or will make one.

http://millermachineandfabrication.com/products.html#southbend

 

[Kernbigo]

I used to make lead screws for J&L thread grinders, yes it will wear out the lead screw if you use mild steel. Get a hold of bearing bronze and make the nut out of it and if you can't find that worse come to worse use brass. Don't use oil lite it is to soft.

 

[Jimsehr]

Google " evanut " an easy way to make a lead screw nut out of Acetal
jimsehr

 

[malar]

How about cast iron? that's what it was made of in the first place.
You could braze it in place when ready.

Also how would you hold a plastic half nut in place?

 

[benmychree]

I have an old SB lathe and the lead screw half nut is worn.
I made one years ago out of mild steel. My concern is will this wear the lead screw if I use it?
Or worse gall. I didn't have any bronze then and have only brass now.
Do I go with the steel and not worry or order some bronze?
I can't up and buy one. It's a 7/8" X 8 TPI acme and none are to be found.

I have repaired South Bend half nuts on an old 9" from 1928; I removed the half nuts, made a fixture to hold them in the closed position, and bored them out about 1/8" on a side and removed about 1/8" from each end; I then made a new nut of bronze, (660 grade bearing bronze) with flanges on each end about 1/4" per side larger than the hole I bored in the half nuts and about 1/8" thick; I then split the new nut in the center and beveled the threads at a 45' angle as the originals were to facilitate closing the half nuts, I then installed the new nuts in the old, bored out half nuts and drilled holes and pinned the new liners into the old housings endwise through the flanges.