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Is my lathe worthless? (Loose Spindle)

TheOldCar

Stainless
Joined
Jul 31, 2011
Location
Utah, USA
Hello everyone! I am a new member, and I apologize up front for a potentially annoying post...

I was kindly given a South Bend 9A that has been used and abused, and I finally got a cheap-o tool post and a box of Harbor Freight carbide bits. I fiddled with some scraps of brass and steel, my first attempts at turning on a lathe, and was quite excited at the process. Also humbled... I have a lot to learn!

The major disappointment I found is the excessive play in the spindle. After reading the posts on this forum and others, I carefully took the headstock apart to find the bearing races (cast iron) totally grooved and scored, especially the chuck side. The spindle, after cleaning up carefully, looks good.

I cleaned the headstock completely, mildly sanded/deburred the bearings, and reassembled with new wicks and fresh oil. I then began removing laminates off the shims, trying different thicknesses. I came to the conclusion that even though I can remove one or two tiny sheets of the shims, if I tighten the stews down to where the spindle won't rattle up and down it just gets too tight for the motor to turn without giving it a tug on the chuck. Even then, the bearing areas get barely lukewarm while running.

I know the shims must be carefully used, not too thick or thin of layers. I also know that this headstock has only one hex screw for each bearing that tightens down on throughout the shims. There is no bolts or adjusting screws behind the bearing races.

My question is: As a paranoid novice, am I crazy to use the lathe (hobby only) as is? If I don't feed the bit too hard and learn how to avoid chatter I seem to be able to turn cool little shapes. I imagine that highly accurate parts will be unlikely with the lathe this way?

Meanwile, I have been thinking I probably need to find another headstock if I want to get serious about using this lathe.
 
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Hi Car,
Twenty four views and no responses, bummer! I think my first SB was a stable mate to yours. It had built up grunge from the late '30s early '40s so I took it to the local and well respected automotive machine shop to have all the major parts "boiled out". While there I asked if anything could be done without a major overhaul and the machinist said he could hone/polish the high spots out but that I would still be left with the grooves. To make a long story shorter, after he was done and the proper shim pack installed the lathe has run very well for eight years , at least as far as bearing problems go. I'm sure your machine has other issues , bad tool post and tooling , but it won't work with bad bearings. You will find a lot of help here.
Karl
 
Thanks for the reply. Maybe I should get my brake cylinder hone and hone the bearings just a tad... I think it will still have the excessive play?
 
don't despair, headstocks are available

Welcome to the joys of old South Bends :D

First, make sure that the spindle lubrication "system" is working.
Start by oiling it VERY thoroughly, and adjusting the shims using a test bar (see here http://www.wswells.com/data/howto/Spindle_Bearing_Adj_9_10k.pdf).

You might want to consider replacing the oil wicks to make sure the spindle is getting enough oil (they can be found new on ebay).

If all else fails... There are a few different models of 9A (i.e. horizontal drive, under drive, others I am unaware of), but headstocks can be found on ebay for not a ton of money. If the rest of the machine is usable it might be worth the investment.

I have one for sale as well, for a horizontal drive.
It is in decent but not perfect shape, and has the "better" segmented bearings.
Send me a PM if you are interested and I will figure out a good price and send you a picture.

Josh
 
"I then began removing laminates off the shims, trying different thicknesses"

There's a specific set of instructions on how to set the bearing clearances
on these machines. If you don't know what they are, say so.

To do this properly you need a good dial gage that preferably reads down to
ten thousanths, and a piece of broomstick.
 
Thanks for the reply. Maybe I should get my brake cylinder hone and hone the bearings just a tad... I think it will still have the excessive play?

No,I don't think your hone is a good idea , not that mine was a perfect solution either. Then , as was mentioned , read up on the correct way of adjusting the shims. Please ask questions , we all learn.
Karl
 
I will get the indicator and test with the broom stick after zeroing for oil film. I think I am supposed to remove the chuck before doing this test, right? Like check the spindle itself without the chuck in place?

Jim is right, I have read the instructions before, but need to find them again here (or wherever I found them before) because I don't know the correct procedure.
 
I forgot to mention: My lathe is an underdrive, and I almost bought the headstock for sale on eBay, but I thought maybe it was listed wrong since it has differences in appearance to mine. I also might just have no idea what I'm talking about!

SOUTH BEND 9" LATHE UNDERDRIVE HEADSTOCK HOUSING CAST | eBay

I keep thinking this is a 10K headstock because of the bolt/screw holes on the back top of the bearings. But again, I obviously am not sure.
 
i had a similar issue,found a horizontal headstock for 175,decided to clean up the scoring with some fine emery cloth and and cleaned it thoroughly,re-shimmed it and filled it with the proper viscosity oil,ran it for a while and checked the tolerance,.0015 is better than my skills will ever need.after an hour on the middle sheaves it is still cool to the touch.i didnt need to buy the kijiji headstock,but i still might.all this info i found right here.take your time,the honing could get out of hand really quick.and most cylinder hones are quite coarse for something like this.the clean-up afterwards could be a nightmare.
 
before you sink a bunch of cash into it- as long as the spindle is good and not scored it will most likely turn just fine once it is cleaned and adjusted to the proper clearances. you may have some cast iron deposits on your spindle- easily removed.
one of my 9" South Bends has scoring on over 75% of the headstock and it turns as well as my other SB`s. that is the beauty of the plain bearings. remember there is no metal to metal contact- the spindle rides on a film of oil. :)
 
Stop right there!

DO NOT run a brake hone through it!

Brake hones just smooth out the pits enough to let the replacement rubber brake cylinder cups last through the warranty period. They do not get the bearing bore straight, parallel, or co-axial with the spindle.

Now that I've told you what not to do, stay tuned. Somebody more knowledgeable than me will tell you what to do.
 
Don't confuse your lathe headstock with an engine block and crankcase! That cast iron headstock can have all kinds of gouges and scratches and still turn a straight clean spindle within tolerances that produces work within tenths of a thousandth. What the other posters have said is profoundly important-if the oiling system is brought up to spec and the head is correctly shimmed, it will turn as good as it did when it left the factory. A cast iron bearing is both accurate and forgiving, especially considering the speeds your lathe will turn. There is no internal combustion heat or chemical action going on, so there is no strain that will cause your spindle or headstock to blow up. Those marks will simply allow more oil to "float" the spindle or expedite the oil returning to the reservoir. Unless you run your spindle for literally days with no oil, you are unlikely to wear it out beyond tolerances for your spindle. Clean it up, replace the oilers and felt, set the shims and spindle "lift" with the broomstick in the spindle, fill with oil and see how it runs. If you don't know what all these procedures are, you will by the time you get it finished. More headstocks have been destroyed by well meaning amateurs than by actual wearing out. Good luck, and don't loose heart. Bill S
 
Holy moly, all of these replies have been more than I ever expected. Thanks to all of you. I am learning more than I ever imagined was available.

Here is what I had finished when I started this post:
Headstock cleaned completely in the parts cleaner, LIGHTLY rubbed the bearing surfaces with some 220 grit, cleaned and polished the nice spindle, and replaced the felt wicks. I then removed two of the laminates from each bearing's brass shim, and replaced the remaining aluminum and brass shims.

He is what I ran out and did quickly today:
Without properly looking up and setting the shims per the instructions, I just went out and tested the spindle clearance with a small "broomstick". I pushed down, set the dial at zero and pulled up. It showed right at .005, which is less than expected, but if I remember right is still too much, right?
Can I put some hope in .005"?

Thanks again for the wonderful help. My redneck skills are getting major help just from the lessons learned in these helpful replies.
 
I would look at the tool bit and how you are chucking the parts
Even if ever thing is loss the part will still cut good and hold size for most parts.


Hello everyone! I am a new member, and I apologize up front for a potentially annoying post...

I was kindly given a South Bend 9A that has been used and abused, and I finally got a cheap-o tool post and a box of Harbor Freight carbide bits. I fiddled with some scraps of brass and steel, my first attempts at turning on a lathe, and was quite excited at the process. Also humbled... I have a lot to learn!

The major disappointment I found is the excessive play in the spindle. After reading the posts on this forum and others, I carefully took the headstock apart to find the bearing races (cast iron) totally grooved and scored, especially the chuck side. The spindle, after cleaning up carefully, looks good.

I cleaned the headstock completely, mildly sanded/deburred the bearings, and reassembled with new wicks and fresh oil. I then began removing laminates off the shims, trying different thicknesses. I came to the conclusion that even though I can remove one or two tiny sheets of the shims, if I tighten the stews down to where the spindle won't rattle up and down it just gets too tight for the motor to turn without giving it a tug on the chuck. Even then, the bearing areas get barely lukewarm while running.

I know the shims must be carefully used, not too thick or thin of layers. I also know that this headstock has only one hex screw for each bearing that tightens down on throughout the shims. There is no bolts or adjusting screws behind the bearing races.

My question is: As a paranoid novice, am I crazy to use the lathe (hobby only) as is? If I don't feed the bit too hard and learn how to avoid chatter I seem to be able to turn cool little shapes. I imagine that highly accurate parts will be unlikely with the lathe this way?

Meanwile, I have been thinking I probably need to find another headstock if I want to get serious about using this lathe.
 
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I forgot to mention: My lathe is an underdrive, and I almost bought the headstock for sale on eBay, but I thought maybe it was listed wrong since it has differences in appearance to mine. I also might just have no idea what I'm talking about!

SOUTH BEND 9" LATHE UNDERDRIVE HEADSTOCK HOUSING CAST | eBay

I keep thinking this is a 10K headstock because of the bolt/screw holes on the back top of the bearings. But again, I obviously am not sure.

He is quite a prolific seller so unlikely to have made a mistake (it is not impossible though), I think the issue is more likely that the headstock is newer/older than yours.

Do you know the model number or serial number of your lathe? Or a photograph of the headstock? Between approximately 1938 and 1942 they were a completely different shape, although I can't see a UMD model A in catalogues from that period. It may have been a B or C converted to A at some point.
 
I cleaned the headstock completely, mildly sanded/deburred the bearings, and reassembled with new wicks and fresh oil. I then began removing laminates off the shims, trying different thicknesses. I came to the conclusion that even though I can remove one or two tiny sheets of the shims, if I tighten the stews down to where the spindle won't rattle up and down it just gets too tight for the motor to turn without giving it a tug on the chuck. Even then, the bearing areas get barely lukewarm while running.

Does the motor have a capacitor? You say the bearings barely get warm when running but the motor won't start turning the spindle without a push. That would indicate to me that someone put a split phase motor on the lathe or that the capacitor in the motor is bad. Slightly dangerous, non-technical test for a bad capacitor, slip the belt off, grab the motor pulley and turn the motor. If you can hold back the motor and make it hum the capacitor is bad, you won't be able to hold onto the pulley if the capacitor is good.
BakoRoy
 
BakoRoy, I never would have thought of that, and I will check the motor. The guy who gave me the old motor said it was wimpy enough that it would be safe for a newbie like me!

So I made some aluminum foil shims and added four to the front shim pack, and five to the back. Bearings tightened down and the dial indicator shows .0035" now when prying with the broomstick. So I will try removing one foil piece each side and measure again. If .003" was the best it ever came to, can I still make good use of this lathe if I learn the proper way to set up bits, feed and speed, etc???
 
aluminum foil can be a PIA, maybe try a cut up beer or pop can for a little more stability- if you can get it to .0015 clearance that would be perfect. the spec is .001 - .0015 for cast iron bearings. better to have too much clearance than not enough.
 








 
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