Old South Bend Lathe Questions

Hello!

Recently, my father and I acquired a South Bend lathe.



A little background about myself, I am an engineering student with a year of being on an SAE team under my belt. I love working in the shops at school, and after coming home for the summer, I decided machinery was not something I could live without. I've made various parts for my SAE team on a few different Clausing lathes, as well as Bridgeports and Acers.

We haven't been able to correctly identify what we have yet, but we did find a serial number. We ordered our serial number card on Grizzly's website, and are waiting to hear back. The number is 19230.

The lathe will need some work. First, some general cleanup and cleaning out the rust. Next, we will need to complete whatever the past owner was trying to accomplish with his pulley system. Then, we will need to fit new leather belts or automotive belts.

Now, for my questions. First, has anyone ever seen a lathe like this? We have been doing as much reading as we can over the last few days but have found very little information.

Second, I would like to upgrade the lantern/rocker style tool post to a quick change. I understand that there are different sizes, but why would we need to get a large expensive tool post if a smaller more economical one fits? The largest thing we will turn will be brake rotors, the rest of our projects will be much smaller. The swing measured to be 24", and a post that size is big money. If we do need a QCTP that large, we will probably just use what we have for now.

Third, I would like to power the lathe with a VFD. We have 220v single phase, and I have found a VFD online that is affordable and can use 220v single phase and provide 3 hp of 3 phase power. The motor that came with the lathe is 3.9 hp. Can we run it under powered? I'd also like to try to make a speed controller, but that is further down the road.

Thanks for any and all help, I'm sure there's probably tons of links on this forum that explain exactly what I'm askign already, I just haven't foud them yet.



EDIT: VFD, Not Phase Converter

What kind of phase converter did you find? With a VFD it is not needed.
A VFD is also a speed control. And most likely convert your single phase to thre phase also.

Made a correction, I meant to say I found a VFD online not a phase converter. I do not physically have one, just shopping for one

that is a genuine 24" O series....I believe a member has a catalog scan so maybe they will be along shortly...and/or you may want to post in the "serial numbers wanted thread" with your pics.

You’ll want to compare notes with PM member “nt1953” on this machine.

From about the beginning of our involvement in WW1 - first half of 1917. I.E., serial 19412 is from May

I'll suppose a 24 (nothing like the way later 16-24) - but they also made 21"

Thumbnails are four page scan of mine from about 1930. If you could read page one, you would see SB wanted the counter shaft to turn 150 RPM - that will be your first goal - to get a big enough sheave or pulley on your upper cone pulley shaft to make that happen with your small motor pulley. I expect a VFD would be handy here to get the motor speed down - rather than having a 3 foot pulley. As to HP, my 13 from a few years later made all sorts of stuff with a 1/3 HP motor

Note the tonnage on these biggies

I'd also like to try to make a speed controller,

Click to expand...

Be smart and kind to the unobtanium heavy bronze spindle bearings - don't exceed 350 RPMs

Here is Mr. Wells 1923 "pocket" catalog that mentions both 24" and 21"

http://www.wswells.com/data/catalog/79JR/cat_79jr.pdf

Of course, you'll need to get it properly lubricated and then run under power to determine whether it's accuracy and capabilities will be adequate for your needs.

Aside from speed of tool changes, QCTP's will set your tool height precisely where you want it "automatically" , whereas a lantern style requires a bit of time and effort to change and set height. If you're not doing tool changes frequently its not as much of a concern.

Do you have the full set of change gears?
Without, you will be unable to do any threading, or regulate your feed rates.

While potentially an interesting find for an old machinery buff, it will be very limited in its usefulness for many smaller shop applications.

Good luck with it.

The lathe came with a lot of gears. I'd assume its most of a complete set. I think we will stick to the tool post it has for now, so I only need to focus on powering, cleaning, and lubricating the machine for now.

A true 24 is a rare beast indeed. I have one, and I know of one more that was posted on this site years ago. Mine has a QC gearbox, but if you have the change gears, you are good to go. Let me know if I can help you in any way.

If you decide you want to sell the steady rest, I would be interested.

PS Don't offer to turn anyone's 9" SB on your lathe .

maybe keep watch on your local CL for an old Drive ALL or Cullman drive, that would solve your issues for powering it....have to be a big 'un tho..

one thing to keep in mind for yer tool post , the larger ones are much more beefier ( is that a word ? ? & the more beef the more rigid
it will be & on a lathe rigid is yer friend
animal

As for the VFD, yes, you can indeed set it up to run the larger motor. Just put in the parameters of the VFD, as in maximum amperage of the VFD output. As well as the 3 HP rating, vs. the 3.9 HP rating. Should also use maximum amperage limit, if it is available. Most of the cheaper drives wont have this though. If Acceleration and Deceleration are available on your particular VFD set them to at least 60 seconds, this will also help with in-rush current. Good luck. That thing is a beast!

Nice heavy lathe. It's great to see it going back into use. It's been resting and waiting for a clean up and oiling. It looks like it's pretty well balanced for lifting in the photo #2

So, Here are some more pictures





And here is the motor's specifications



So, I misread the label. It is a 3 Hp motor. We are still trying to figure out how to power it. I've been looking for VFDs and doing as much research as I can, but It seems that it isn't easy to take single phase 220v and make three phase 440v. The motor only spins at 1710 rpm, drawing 3.9 amps. After some quick searching, I'm starting to think maybe I should just get a new/used single phase 220v motor. 3hp models that use more current seem more readily available, but most of the motors I've found spin much faster, at 3000 rpm or more. If I could find a motor that spins slower at its peak power, that would be ideal, but I'm starting to think maybe I should buy a faster motor and throttle the speed instead of changing belts. Is my logic flawed? Should I be worried about overheating a motor if I am not running it very fast?

Also, after doing more reading, I think we will stick to the Armstrong lantern post for now. For what we are doing, taking the time to set height isn't a big deal. I just need to buy some tools now.

Next, I need to figure out how to keep this thing oiled. We bought a belt sander off a guy today who just so happened to be an old machine repair guy. He said that oilers are usually threaded. Ours are not, they just look like little brass nipples.



I'll keep searching, but maybe someone already knows?


We started to clean everything today. Something is wrong with the tailstock, I'll grab some pictures tomorrow. I ordered 16oz bottles of the four oils last night on ebay too. I've been using WD-40 and scotch brite to gently clean the ways and other surfaces. The more we dig into the machine, the better it gets. Everything comes apart pretty easily, and I think it has been well maintained. I'll try to post again tomorrow

I've been using tool holder's & HSS insert's from these guys for a couple of years & really like them
https://www.arwarnerco.com/
animal

that monster SB has a top speed of 355rpm with a countershaft speed of 150rpm.

Just use your lantern post and HSS, you are going to spend more time in the cut than anything, making a QCTP a moot point....not such a big deal to spend a couple minutes setting up your tool in this case.

IMO you have two choices to power it, use the original cones to achieve the original speeds or find a Drive All or Cullman type transmission...if you can find one.

It's a beast for sure.

Say you DID run the 1710 at 60Hz

Say further that your motor pulley is 4"

You would need a 45.6"diameter pulley on the upper cone pulley shaft to get to 150 RPM

A very good reason for a gear box such as Drive All

We got our serial number in! I will post in the serial numbers thread eventually. Our lathe turns 100 on sunday.



For the motor, I'm pretty sure I want to buy a new single phase and make a speed controller. I looked into drive alls and Cullman gear boxes and they look cool, but I couldn't find anything used and I can't afford a drive all new. I'd sooner rig up an automotive transmission. My current plan is to take some measurements and find a way to make the counter shaft spin at 150. I might even eliminate the countershaft entirely, and just run a pulley from the motor to the main shaft, but I haven't gotten that far yet. I need to take a few more measurements and sit down and do some math.

The tailstock has been a bit of a problem. When we first got it, the wheel would spin but nothing would happen. I took the wheel off, and found that the keyway was sheared. My dad and I took the guts of the tailshaft out and have been soaking it in oil, but it is seized. It doesn't look bad at all, we are thinking that a previous owner just tightened it as hard as they could until the key broke. Either way, we have been soaking it in oil and trying our best to turn the inside threaded section without causing any damage.






Any ideas? I don't have a picture, but where the tool goes in on the tail stock shouldn't there be a place for the morse taper to sit? If I look down the shaft, I see a threaded shaft and a gap all the way around it. The inside is tapered but there isn't anything that would keep a chuck from spinning. I'll take more pictures tomorrow.

you can get away with eliminating the countershaft on the little guys sometimes but on this one you'll spend more money on what's required to do it than if you bought a new Drive All.

Can't effectively use a speed controller on a single phase motor at this size and speed range either.

Try giving the quill a good soak in warm oil for a while, then stick the quill into a bucket of cold water and use a little gentle heat on the screw part..the cold will shrink the quill a bit and the heat will expand the screw...i know that sounds counterintuitive but chances are it's just the shoulder is torqued down against the quill...once you get it apart cut a gasket or use a thick o ring and slip it on the screw to keep it from happening again.

If that doesn't work then simultaneously tapping the screw part(with a rod through the end with the morse taper) while also turning the screw from the other end may do the trick...just gotta find a good way to hold things without damage and probably easier with two guys working together.

ps- try posting a wanted ad in the for sale/wanted section for a drive all, I see them every so often for a few hundred bucks, someone just might have one laying around.

The tailstock screw turns in the opposite direction from how you think it does

Oh, and the taper is all it takes to keep the tool from spinning, thats how tapers work

allan