South bend 9 restore question

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Naiveambition

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As u may have seen on another thread, I inherited a south bend lathe and am in the process of cleaning and painting it . I'm up to the spindle assembly, and need an attack plan. I am getting ready to paint and degrease , my usual attack plan was easy-off sprayed on then hose off. I'm worried about the runoff of the cleaner and dirt, paint, WATER etc. getting into the bearings.
The second option Is take the headstock apart and and follow my usual plan. My concerns lay with the bearing placements. They do have shims and are split bronze so, can I just pop it off do my cleaning, then put back together the same way and not expect problems. Or is it u take it apart and u have to rebuild.

image.jpeg
 
This sort of answers your question and also adds another train of thought.

If I was in your situation, I would be inclined to disassemble and inspect everything, just to be sure there is nothing else that needs to be done now or in the future. I don't know that much about your lathe and how easy or hard it would be to do this, but you might avoid having to take it apart later which might mess up your cosmetic restoration in that process.

Besides looking for scoring, loose fits, etc., you are also looking for clogged lubrication pathways and places where dirt and swarf can get into things.

If it's too hard to take apart and reassemble with proper clearances and alignments, then get what precision measuring tools you can to put numbers on the conditions of things as they are.

--ShopShoe
 
The problem with disassembling it is that there are shims under the caps for bearing adjustment so you have to keep those in the correct location. There are ways to check head wear. Do a search for South Bend spindle bearing check but probably it is OK.
 
Look at:
[ame]https://www.youtube.com/watch?v=K3c0iwFgORo[/ame]
Also get Keep Your Lathe in Trim Bulletin H4, Available on the internet
 
Not sure on the South Bend but on other brands I have left the bearings/bushings in place. Loosen all set screws or nuts holding gears and pulleys in place and slide the spindle out. Clean things up, paint and slide it back together. You may need to loosen the bearing caps a little but should not have to take them all the way off.
 
I vote for leaving it alone and tear it apart only if you have trouble later. The painted parts can always be repainted.

My Southbend 9 consumes oil but it has been like that for the last 10 years during my ownership and it still works just fine.

It's like having an old car... you can clean it up and use it or you can take it apart, restore it and show it.
 
Thank for all the replys fellows. I went with not tearing it apart. I agree that if needed I can repaint later. I used easy off to remove paint , grease, then compressed air dry to stop flash rust. Wiped with grease remover, finished with a small brush.
My original plan was to use bondo and make it a nice paint job. I did bondo the tail stock and the back gear covers also. So when time comes to replace the bearings I will go all out again and repaint, bondo the entire unit. This cleanup was to learn about the machine while removing 40 years of crud.lol.
Here's a pic where I'm at now. I'll try to get better ones later. iPad cams not that great:eek:
On a side note , I've never had a lathe with bronze bearing. How much resistance should be expected,or normal. The spindle does turn nice and smooth with no rough feelings just seems a little tight feeling. Oiling it did help some but just wondering as all my other machines have roller bearings.

image.jpeg
 
Should turn freely by hand when cold.Run for a short period and check
with hand on temp.Bearings may tighten up when hot.Old school
machinists think bronze bearings are better than ball brgs.better finish
if set correctly
 
South Bend has been a workhorse for years and have a great reputation for being rugged. As I understand almost all WW II ships had a SB lathe and many defense factories used SB lathes. Not super precision but hard working.
 
I was helping an old friend of mine clear his shed - he (preciently enough) wasn't expecting to be needing it much longer. On his South Bend 9" lathe, the plain headstock bearings were held in sprung cast iron (!) caps which were only split on one side, with a bolt through the split. I was surprised how easy it was to take the play out of it, and then go too far and render it tight. I would suggest slackening yours off until you can rattle the spindle up and down, and then do it up until this *just* stops.
 
Was able to apply power to the spindle and seems ok. The real test will come when cutting so we will see what happens.
I still need to finish the 3 jaw chuck and make a bolt for the swivel in the compound. I did finish all of my major cleaning and painting. Am really happy so far. Here's some pics of the lathe as of now. View attachment ImageUploadedByModel Engines1491257335.441707.jpgView attachment ImageUploadedByModel Engines1491257352.184624.jpgView attachment ImageUploadedByModel Engines1491257369.362435.jpgView attachment ImageUploadedByModel Engines1491257383.707903.jpg
Only problem is the pulley system in the rear bounces as it turns. Only weight is used to hold tension on the belt so that will be addressed. Any thoughts
 
I _think_ these normally have a rather long eccentric-cam lever to lock the countershaft, with a kind of threaded turnbuckle in the middle to set the tension. Maybe you've been there, but you can look it up on 'lathes.co.uk' which will give you lots more info. From there I note that someone seems to have replaced the very odd (but original) setup of a v-belt driving a plain wheel on the countershaft, with a v-pulley, on yours.
 
I'll add my kudos to the job you are doing with this. I agree that the the drive systems looks like it's been modified.

I believe that mrpete222 on YouTube has some videos on cleaning up Southbend lathes where you might see how the drive system is configured.

--ShopShoe
 
My old SB has a tensioner for the flat belt so that you can easily change speeds. However, given the low hp of my motor I leave mine at the lowest chuck rpm possible. Your set up should work OK as long as you leave it in one setting. I think that mine runs at 600 rpm.

The nice part of the flat belt drive is that it will slip if you crash a tool into a work piece. It's a very forgiving set up.

That said, the whole machine is past its prime when it comes to parting off. I need to lock down everything for rigidity and pray when making the cut. Some days a hack saw and end facing afterwards works better.

Still, I love my 1940s SB even with its limits. Mine is not a clean as yours so you win.
 

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