South Bend 9" Half Nut Replacement

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Big Hairy Animal

Plastic

Joined

Oct 8, 2016

• Nov 4, 2016

• #1

Hello South Bend Universe! The half nut on my 1935 SB9C is pretty worn out and I'm looking at options. Boring it out and setting an insert is on my list but I have very little meat to work with and the mill at work is hard to get time on.

I also found this Hercules part in Australia. The vendor says it's a 1-1 replacement for my SB9C but I am hoping for your opinions and expertise to confirm.

 

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promacjoe

Stainless

Joined

Jan 10, 2009

Location

Tn USA

• Nov 4, 2016

• #2

At one time, there was someone rebuilding them here. You sent the old Half nuts to them, they would either rebuild them and send them back or send you a replacement set that was already rebuilt. Alternatively you can have a look at,

http://www.lathes.co.uk/page8.html

Scroll down and look for clamping nuts for the Boxford / South Bend. This is a UK site. And yes Hercus and Boxford are clones of the South Bend. and many parts will interchange.

also make sure you look through the above site. Specifically at,

http://www.lathes.co.uk/index.html

there is a lot of good information about South Bend's there along with all of the clones that were available. This is a great resource for identifying and researching machinery.

Stay safe and have fun.

Joe.

 

K

Ken-Bergen

Cast Iron

Joined

Jun 7, 2012

Location

Chilliwack BC Canada

• Nov 4, 2016

• #3

That link is for metric half nuts.
Do you have a metric lead screw?

 

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iwananew10K

Diamond

Joined

Sep 12, 2010

Location

moscow,ohio

• Nov 4, 2016

• #4

Check your leadscrew...since your machine started off life as a 405 it might have a left hand thread.

 

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promacjoe

Stainless

Joined

Jan 10, 2009

Location

Tn USA

• Nov 4, 2016

• #5

Ken-Bergen said:

That link is for metric half nuts.
Do you have a metric lead screw?

Click to expand...

Please read again. "NEW CLASP NUTS for the leadscrew – inch or metric".

stay safe and have fun.

Joe.

Sorry, reference the room post. My computer and the Internet has been kind of goofy lately, probably because of the election. I should read the quote, instead of just reading my reply.

 

Last edited: Nov 5, 2016

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iwananew10K

Diamond

Joined

Sep 12, 2010

Location

moscow,ohio

• Nov 5, 2016

• #6

I can read.

In an earlier thread his machine started out life as a 405, and there are a few things unique to at least some of the models, among them 20DP change gears and a 3/4" LEFT hand acme Leadscrew, obviously a later right hand set of half nuts will not work IF he has a left hand screw and would be a fine waste of money.

http://www.lathes.co.uk/southbendmodelfive9inch/

 

jlrii

Hot Rolled

Joined

Dec 17, 2007

Location

Massachusetts, USA

• Nov 5, 2016

• #7

promacjoe said:

At one time, there was someone rebuilding them here. You sent the old Half nuts to them, they would either rebuild them and send them back or send you a replacement set that was already rebuilt.

Click to expand...

That was jayhawkman he still has them on ebay.

9" south bend lathe half nuts lot #5 | eBay

also contact info here

http://www.practicalmachinist.com/vb/south-bend-lathes/9-10k-10l-crossfeed-screw-nuts-sale-until-1-jan-17-a-326113/

JR

 

B

Big Hairy Animal

Plastic

Joined

Oct 8, 2016

• Nov 5, 2016

• #8

jlrii said:

That was jayhawkman he still has them on ebay ...

Click to expand...

I posted to and texted jayhawkman last week and haven't heard back. That eBay link is grand though - I'll try and get some final details there through eBay.

iwananew10K said:

Check your leadscrew...since your machine started off life as a 405 it might have a left hand thread.

Click to expand...

Best I can tell it's a 3/4" - 8 TPI Right Hand Thread. Identifying Right Hand thread is so simple that I fear it might also be easy to mistake but I checked a few times.

If I identify that the eBay link is indeed 3/4"-8 then I guess I found my fix. Damn expensive but I guess that's how supply and demand works ...

Thanks everyone!

 

K

Ken-Bergen

Cast Iron

Joined

Jun 7, 2012

Location

Chilliwack BC Canada

• Nov 5, 2016

• #9

Your Ebay link says

metric half nuts- clasp nuts

Click to expand...

3/4"-8 is not metric.

 

Yan Wo

Stainless

Joined

Jan 22, 2014

Location

Highland, Utah, USA

• Nov 5, 2016

• #10

Ken-Bergen said:

Your Ebay link says 3/4"-8 is not metric.

Click to expand...

OK, how about M19 x 3.175?

 

K

Ken-Bergen

Cast Iron

Joined

Jun 7, 2012

Location

Chilliwack BC Canada

• Nov 5, 2016

• #11

Yan Wo said:

OK, how about M19 x 3.175?

Click to expand...

Well you certainly mangled that quote.
If the lead screw is Imperial and the half nuts Metric no amount of just about fudging is going to make them work together.

 

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bob531

Aluminum

Joined

May 9, 2015

Location

U.K Cumbria

• Nov 7, 2016

• #12

Im busy doing up to sell a spare 9 A which is older than the newer 1964 one i use, the half nuts are worn on this older 1941 model. I understand the process of repairing them with a threaded bronze bobbin etc... but does anyone have any photos of an easy clamping arrangement for boring out the old threads and how do you centre the arrangement for boring?

The shape of them are pretty awkward and there isnt really a clear circumference to indicate in a threaded hole.??

i`d prefer to do it on a seig type mini mill i have as im still collecting tooling for the larger mill i own .
thanks