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Got a good apron for the model A southbend lathe

The first apron I bought off of ebay was a piece of crap. It was totally worn out, and the selector handle was broken in shipping. After completely cleaning and stripping it down I ended up returning it to the the jackass I bought it from, and getting my money back.

Another one showed up soon enough, and this time I asked some important questions and landed a good deal.

So... back to the stripping tank!

Stripping the old paint of the south bend model A 9" lathe apron

The apron was a little rusty, and had apparently been painted with latex house paint (!). But other then that, it was in great shape. Well at least compared to the first one.

rusty apron from southbend workshop 9" model a lathe

The front looks pretty rusty.

The back looks much better. I think that despite appearances it is going to clean up well.

First I pop out the taper pin on the handwheel (checking carefully to make sure I am hitting the big end).

removing the taper pin from the south bend nine inch lathe apron handwheel

Next step is to flip the apron over and knock out the pin holding the key in the leadscrew worm.

rmoving the pin holding the key in the leadscrew worm on a 9 inch southbend lathe

Then the retaining nut can be unscrewed. I did find that there was a slight burr on the threads around the pin hole. It took a bit of force to get the retaining nut to turn but once it started going it was fine.

And... off

leadscrew worm retaining nut on southbend nine inch lathe apron

Then you pull the clutch pieces out by loosening the LEFT HAND THREAD screw in the start handle. LEFT. HAND. THREAD. This is why so many aprons on ebay are missing the screw. It does not take much torque turning the wrong way to break it off.

clutch star knob on south bend 9" lathe apron LEFT HAND THREADED SCREW!

Once the clutch shaft is removed (I don't have photos of that but it basically just falls out) the worm gear is loose and you can turn the worm and the gear to carefully remove the worm. It is a bit tricky, but as long as you keep an eye on the end of the worm threads you can wiggle it out.

removing the leadscrew worm from a south bend workshop 9" lathe apron

Once the worm is out you can remove the worm gear by just pulling it out. Then the other gears come out. Remember to remove the retaining clip on the the cross feed drive gear.

retaining clip on cross feed drive gear from southbend nine inch workshop lathe apron

If you want to remove all the shafts (as I did) you need to find the  various set screws that hold them in place. this one is on the "top" edge of the apron and locks the short shaft holding the cross feed drive gear. In my case someone had pounded on the shaft with a hammer. No doubt because they did not see this set screw. I will need to clean the shaft up on the lathe. When everything else is done of course.

cross feed drive gear shaft set screw southebend nine inch workshop model A apron

This one hold in the shaft for the gear that drives the handwheel pinion against the rack when using the longitudinal power feed.

On the bottom of the apron is a set crew that presses in a spring and steel pin to keep the half nut handle from falling out. Make sure you remove everything so that the pieces don't fall out later and get lost.

removing the half nut retaining assembly 9 inch south bend model A or B lathe apron

Here is the complete set.

half nut retaining assembly 9 inch south bend model A or B lathe apron

That is pretty much it for the tricky parts. Here is everything laid out and ready for clean up and inspection.

completely taken apart apron from a south bend model A or B 9" workshop lathe

Next up is the quick change gear box!

I planned to take lots of pictures and document every step.
I didn't.
When I remembered to take a shot I was usually too greasy, and when I was busy I rarely remembered.
Here is what I did manage to shoot.

1. this is the apron as I received it from ebay after running it though my lye bath. I did some partial disassembly before shooting these.

backgear, eccentric, and headstock for southbend nine inch lathe

I realized at some point that once things were apart even photos would not necessarily be enough. I really like this way of working, I lay out the parts as I remove them and make notes as to how they go together. Then I shoot  a picture of the whole thing for future reference.

Here is the back gear and eccentric showing how it attaches to the headstock.

Lots of people buy old lathes and other machine tools and spend too much time fixing them up with no clear idea of what the intend to use them for. Right? Hello, anyone?

Anyway I started breaking the individual components down to clean them, prep them for painting, and to see how they worked. As far as I am concerned there is no better way to learn about a tool then taking it apart and then putting it back together. The putting it back together part in particular.

I am enjoying the process of taking apart the Southbend lathe, and especially enjoying the opportunity to make custom tools as needed.

Here is a screwdriver cut to fit the nuts on the end of the cross feed screw.

I started looking for the parts I need to convert the Model C to a Model A. As with most things, there is a lot to learn about buying on ebay. I spent some time watching without bidding, and looking at the prices of completed auctions. Then after I thought I had a handle on what I needed to spend I ran across what looked like a great deal. The seller had an quick change gear box with the keyed leadscrew and associated gearing. The only thing was that it was for a longer bed.

I want to completely strip the South Bend Lathe down to the bare metal and then repaint it. This will mean taking out every screw and taper pin (more on those later) and then using some kind of paint remover to get down to the bare metal. I hate organic chemical strippers. They work great, but long ago I got sensitized to them by being cavalier about wearing gloves. Nowadays even a drop on my hand feels like a burning match.

After taking the lathe down to its major assemblies I have decided to strip the paint off and do a full conversion from Model C to Model A.


I am going to start hunting for parts on ebay while I clean the ones I will be keeping.

Next in line for disassembly is the spindle. At the gear end there is a threaded split collar that retains the spindle and is used to remove end float. It has a set screw that you have to loosen, then you need to know it is threaded or else you will try and pull it off (which you can't). Behind the collar is a fiber washer and a steel washer. Once all of this is removed then you loosen the cap screws (or bolts on some) sqishing the bearings on their shims, and then the only thing holding the spindle in place is the very tightly fitted bull gear and its key.

I took a bunch of pictures of the basic tear down process. This Model C South Bend is not a particularly complex lathe. It has a plain bearing spindle, a simple backgear on an eccentric shaft, a flat belt cone pulley driven from a separate countershaft, and a very basic apron with little more then a handwheel driving a gear against a rack and a simple set of half nuts. I am lucky in that this headstock has later style bearings with grooves cut in them to reatin more oil (I think) and provide a slightly higher top end speed.

So I started tearing into the lathe out of a desire to A. figure out how it all works, and B. to clean up all the gunk, dried oil, and swarf.

Almost immediately I found the first problem which is that the headstock drive cone pulley has a broken tooth where it engages the back gear. Looking on ebay I see that I can probably get one for $40 or so, and that is probably what I will do.

I set up google alerts on craigslist for any mention of south bend lathes, southbend lathes, southben laths, and any other silly misspellings. After waiting several months, missing several reasonable deals, and ignoring several apparently solid gold south bend lathes in "perfect" shape, I finally found what seemed to be a good deal. I drove about two hours to get it, and had another enjoyable conversation with a fellow machine tool fanatic.

When I bought this mill it came with an overarm support but no means of holding it to the overarm proper. There was a hole through the support casting at a right angle to the overarm hole, and it was clear from looking at pictures of other peoples mills that there was supposed to be a cotter there to hold it in place. I decided to try and make a cotter to fit, and looked online for information on how to do it. Not much showed up, although I got enough detail to think I could figure it out.

When I picked up the mill I also got a "manual" which is more marketing material then anything. I am attaching it here in case anyone else has one of these and finds it useful.

I have also found a bunch of links on the web that talk about the mill.

This was a fun one. I saw a listing on craigslist for a small horizontal milling machine. It was about two hours south of Seattle in a little town called Castle Rock. The photos looked pretty cool, and it had a shop made vertical head and a bunch of tooling. I had never used a horizontal mill, but after some very brief research I decided I wanted it. The price seemed reasonable, but what did I know.

I found an old Taiwanese Jet 9X20 lathe on craigslist for $600. When I went to take a look it had obviously been neglected and there were some broken parts. I talked the guy down to $500, loaded it in the Honda CRV, and headed home happy. I bought some replacement parts, and made a new compound clamp for it, and it worked OK. Here is what it looks like.

After a hiatus of some 25 years I have once again gotten interested in machine tools. I am trying to put together a shop that will let me make anything that comes to mind. I am starting with a lathe, a small MIG welder, and some kind of mill. And a horizontal band saw. Oh and an arbor press. There is probably more, but that is a good start.