Upgrade

Printable View

Feb 27, 2017, 05:24 PM
mr95gst

South Bend 9" model 405 Lathe - Refurb / Restoration / Upgrade

I found an ad on craigslist for a $100 South Bend lathe. It had no pictures, but I bought it sight unseen. I figured at $100 it was worth the risk. When I picked it up that afternoon, I found out it was the sellers Dads and had been sitting in a barn for at least 20 years. It had significant rust and the apron was broken into 3 pieces. The head still moved but everything else was stuck. I initially thought it was a 9" model C but I later found out it was a model 405 with a 4' bed. The serial number looks like it was manufactured around 1935. Once the excitement of the purchase wore off, I began to have serious doubts. I figured I might be able to salvage some of the pieces, but most of it would be a lost cause. Spoiler Alert: I got the entire thing working again.

This is what I started with:

http://i149.photobucket.com/albums/s...e/IMAG0515.jpg

http://i149.photobucket.com/albums/s...e/IMAG0516.jpg

http://i149.photobucket.com/albums/s...e/IMAG0554.jpg

http://i149.photobucket.com/albums/s...e/IMAG0550.jpg

http://i149.photobucket.com/albums/s...e/IMAG0552.jpg

http://i149.photobucket.com/albums/s...e/IMAG0553.jpg

http://i149.photobucket.com/albums/s...e/IMAG0547.jpg

I started by disassembling, degreasing, electrolysis for rust removed, and a lot of hand scrubbing.
http://i149.photobucket.com/albums/s...e/IMAG0603.jpg

http://i149.photobucket.com/albums/s...e/IMAG0543.jpg

http://i149.photobucket.com/albums/s...e/IMAG0561.jpg

http://i149.photobucket.com/albums/s...e/IMAG0560.jpg

http://i149.photobucket.com/albums/s...e/IMAG0562.jpg

Then priming and paint:

http://i149.photobucket.com/albums/s...e/IMAG0571.jpg

http://i149.photobucket.com/albums/s...e/IMAG0593.jpg

http://i149.photobucket.com/albums/s...e/IMAG0591.jpg

http://i149.photobucket.com/albums/s...e/IMAG0589.jpg

http://i149.photobucket.com/albums/s...e/IMAG0594.jpg

Next I started reassembly:

http://i149.photobucket.com/albums/s...e/IMAG0924.jpg

http://i149.photobucket.com/albums/s...e/IMAG0925.jpg

I needed a bench to mount the lathe so I took a break to do some wood working. The top is made from pine 2x4s and the legs are 4x4s.

http://i149.photobucket.com/albums/s...e/IMAG0955.jpg

http://i149.photobucket.com/albums/s...e/IMAG0954.jpg

The original motor and drive assembly was lost at some point years ago. When I bought the lathe it came with an replacement AC motor and a horribly put together tensioning system. I decided to remake something out of tube steel that looked a little more like the original South Bend configuration. I decided to go with a DC treadmill motor and a variable speed DC drive. With the DC motor, I don't need step pulleys and I didn't have to configure a complex belt tensioning device. I cast the motor mount and motor pulley from aluminum scrap.

http://i149.photobucket.com/albums/s...e/IMAG1042.jpg

http://i149.photobucket.com/albums/s...e/IMAG1040.jpg

http://i149.photobucket.com/albums/s...e/IMAG1039.jpg

http://i149.photobucket.com/albums/s...e/IMAG1041.jpg

After running the lathe a bit, I noticed the motor was getting hot. This is a 12v motor and shroud I made that slips onto the back side of the motor.

http://i149.photobucket.com/albums/s...e/IMAG1120.jpg

http://i149.photobucket.com/albums/s...e/IMAG1127.jpg

This is a junction box that houses the on/off switch, speed controller, fan power supply and tachometer.
http://i149.photobucket.com/albums/s...e/IMAG1101.jpg

http://i149.photobucket.com/albums/s...e/IMAG1103.jpg

This is the tachometer sensor and mount. The rear pulley is only slightly larger than the pulley on the spindle. That means the spindle RPM is only slightly faster than my tachometer reading. I was really just trying to get a ballpark reading.

http://i149.photobucket.com/albums/s...e/IMAG1102.jpg

http://i149.photobucket.com/albums/s...e/IMAG1122.jpg

The lathe came with an independent 4 jaw chuck. I got fairly proficient with it, but I wanted a self-centering 3 jaw. The problem with a model 405 is that the spindle thread is 1-3/8" -10. No one make an adaptor or back plate. To my knowledge South Bend was the only company to use that thread on a spindle and they only did it for a couple years. I used decided to use the small back plate from the 4 jaw to make an adaptor. I cast a 6.5" disk from aluminum and turned it to accept the old back plate on one side and the new 3 jaw on the other.

http://i149.photobucket.com/albums/s...e/IMAG1077.jpg

http://i149.photobucket.com/albums/s...e/IMAG1078.jpg

http://i149.photobucket.com/albums/s...e/IMAG1079.jpg

http://i149.photobucket.com/albums/s...e/IMAG1080.jpg

http://i149.photobucket.com/albums/s...e/IMAG1082.jpg

http://i149.photobucket.com/albums/s...e/IMAG1081.jpg

http://i149.photobucket.com/albums/s...e/IMAG1084.jpg

http://i149.photobucket.com/albums/s...e/IMAG1121.jpg

http://i149.photobucket.com/albums/s...e/IMAG1117.jpg

This is the lathe all finished up. I have done several hours of turning on it at this point. I have mostly done aluminum. So far it has exceeded my expectations. Everything is solid and the surface finish is great. South Bend produced a quality and capable machine 80 years ago!

http://i149.photobucket.com/albums/s...e/IMAG1125.jpg

http://i149.photobucket.com/albums/s...e/IMAG1123.jpg

http://i149.photobucket.com/albums/s...e/IMAG1119.jpg

http://i149.photobucket.com/albums/s...e/IMAG1116.jpg

http://i149.photobucket.com/albums/s...e/IMAG1115.jpg

Here is a piece of cast aluminum I turned before I had the 3-jaw chuck.
http://i149.photobucket.com/albums/s...e/IMAG1069.jpg
Mar 1, 2017, 06:07 AM
DIYer


Thanks mr95gst! We've added your Lathe Restoration to our Lathes category,
as well as to your builder page: mr95gst's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-lathe-restoration-2"> <img src="/uploads/166377/homemade-lathe-restoration-2.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-lathe-restoration-2">Lathe Restoration</a> <span> by <a href="http://www.homemadetools.net/builder/mr95gst">mr95gst</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/lathe'>lathe</a>, <a href='http://www.homemadetools.net/tag/restoration'>restoration</a> </div> </div> </div> </div>
Mar 1, 2017, 06:10 AM
DIYer


Thanks mr95gst! We've added your Lathe Bench to our Dollies and Stands category,
as well as to your builder page: mr95gst's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-lathe-bench-4"> <img src="/uploads/166381/homemade-lathe-bench-4.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-lathe-bench-4">Lathe Bench</a> <span> by <a href="http://www.homemadetools.net/builder/mr95gst">mr95gst</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/lathe'>lathe</a>, <a href='http://www.homemadetools.net/tag/table'>table</a> </div> </div> </div> </div>
Mar 1, 2017, 06:13 AM
DIYer


Thanks mr95gst! We've added your Lathe Motor Replacement to our Lathes category,
as well as to your builder page: mr95gst's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-lathe-motor-replacement"> <img src="/uploads/166385/homemade-lathe-motor-replacement.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-lathe-motor-replacement">Lathe Motor Replacement</a> <span> by <a href="http://www.homemadetools.net/builder/mr95gst">mr95gst</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/lathe'>lathe</a>, <a href='http://www.homemadetools.net/tag/motor'>motor</a> </div> </div> </div> </div>
Mar 1, 2017, 06:16 AM
DIYer


Thanks mr95gst! We've added your Lathe Adaptor Plate to our Lathe Accessories category,
as well as to your builder page: mr95gst's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-lathe-adaptor-plate"> <img src="/uploads/166389/homemade-lathe-adaptor-plate.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-lathe-adaptor-plate">Lathe Adaptor Plate</a> <span> by <a href="http://www.homemadetools.net/builder/mr95gst">mr95gst</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/lathe'>lathe</a>, <a href='http://www.homemadetools.net/tag/adaptor'>adaptor</a> </div> </div> </div> </div>
Mar 1, 2017, 06:19 AM
DIYer


Thanks mr95gst! We've added your Cooling Fan Shroud to our Lathe Accessories category,
as well as to your builder page: mr95gst's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-cooling-fan-shroud"> <img src="/uploads/166393/homemade-cooling-fan-shroud.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-cooling-fan-shroud">Cooling Fan Shroud</a> <span> by <a href="http://www.homemadetools.net/builder/mr95gst">mr95gst</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/fan'>fan</a>, <a href='http://www.homemadetools.net/tag/lathe'>lathe</a> </div> </div> </div> </div>
Mar 1, 2017, 06:16 PM
ragsflh

thanks,looks great
Mar 2, 2017, 08:59 AM
Wmrra13

Nice work! I'm very impressed, particularly with the VFD drive system and 3-jaw mounting solution - even the bench is really nice!
Please show us more of your foundry techniques.

Cheers,
Tyler
Mar 3, 2017, 02:01 AM
pfredX1

I can't believe they still wanted $100 for that lathe in the shape it was in. But hey you got it going again. I'm surprised they even knew it was a lathe. I can see why they didn't post any pictures of it too.
Mar 3, 2017, 09:50 AM
olderdan

Great restoration job mr95gst, if my SB 9B is anything to go by you will be well rewarded these are quality machines.
It looks as though all that muck on it did you a favor in the end.
I notice a lack of tumbler reverse so I can recommend a reversing electric leadscrew drive (No 1 mod for me).
Regards
Olderdan
Mar 4, 2017, 03:39 AM
rossbotics

That's a great job you did there on the restore, I myself have 4 older metal working machine tools that I have restored back to there originality, I'm from the old school and this is the kind of equipment I was taught on, I personally do not want anything but this kind of equipment in my shop, this stuff is indestructible, this summer I'm going to restore my 6913 Clausing lathe.
Love the back plate casting and VFD, did it have all the change gears?

Here is a link to my shop and some machines I restored
https://rossbotics.wixsite.com/machiningtechniques

You did a great job, keep up the good work
Mar 4, 2017, 04:16 AM
tonyfoale

7 Attachment(s)

Quote:

Originally Posted by olderdan

I notice a lack of tumbler reverse so I can recommend a reversing electric leadscrew drive (No 1 mod for me).
Regards
Olderdan

Alan,
Are you talking about a synchronised leadscrew drive that would enable screw cutting or a free running system just for turning/facing feed?
if synchronised, how are you doing that. I ask because I am thinking of doing that and there is no point reinventing the wheel.

Some years ago I bought a lathe that looked to be in bad rusted shape, but it turned out that it had spent years unused in a corner near the grinding area before being put out to pasture. The rust was mainly on the old grinding swarf and so when cleaned up there was little rust on the machine. Here are some before and after shots.

Attachment 16840 Attachment 16841

Attachment 16839 Attachment 16835

Attachment 16836 Attachment 16837

Attachment 16838
Mar 4, 2017, 09:22 AM
olderdan

2 Attachment(s)

Tony,
I am no help to you on this as my leadscrew drive is just for plain turning only.
Having said that I find it a vast improvement as its variable speed and adjustable during a cut.
I used a new golf cart 12v motor and gearbox powered by a battery charger, to be honest I do not have the knowledge to create a synchronised system.
That lathe you restored is one solid piece of machinery, and a very nice job you made of it.
Attachment 16842
Attachment 16843
Mar 4, 2017, 10:22 AM
Vyacheslav.Nevolya

You did a great job. Thank you for sharing.
Mar 5, 2017, 10:56 AM
tonyfoale

2 Attachment(s)

Quote:

Originally Posted by olderdan

Tony,
I am no help to you on this as my leadscrew drive is just for plain turning only....., to be honest I do not have the knowledge to create a synchronised system.

There are many ways to do it. The easiest would probably be to put an encoder on the spindle which will tell you where that is. I am actually waiting for an encoder to arrive and I attach a pic. of the mounting that I have made for it. Then use a stepper motor on the screw, or geared down to the screw. Then it is only a matter of training some electrons to feed steps according to the gear ratio "spindle to screw" that you need. An Arduino with a stepper motor shield could run the electron circus at very low cost. Although this is probably the easiest way to do the job, it is not the best. If you use the half nuts for screw cutting you still have the need to engage them manually at the correct moment and you still have the reversing out problem when cutting metric threads with an inch lead screw and vice-versa.
One better method using the same basic hardware would be to define a "home" position of the saddle, which the control system would find on each startup. Then the position of the saddle is always known relative to "home", as long as you don't open the half nuts. If you accept not opening the half-nuts then you might as well replace the nuts and lead-screw with ball nut and screw (not overly expensive now). The downside is that you are then prevented from moving the saddle manually so you add a pulse wheel (see pic) to the apron.
Now that you've got that far you might as well do the same to cross slide and then you have a full CNC lathe.
Personally I don't like trusting steppers to never miss a beat and I prefer using servo motors and linear slides for position, but the cost is higher than the first option and fitting the slides is not always easy.

Attachment 16857
Pulse wheel.

Attachment 16858
Bracket for rotary encoder. Smart Alex will note that it prevents long stock being used. That bracket was designed to hold an encoder with none of the backlash or flex associated with a belt driven unit. This is for a specific accurate measurement task and not for general lathe work.

Quote:

Originally Posted by olderdan

That lathe you restored is one solid piece of machinery, and a very nice job you made of it.

I hadn't much of a workshop for 20 years after I moved from England to Spain, but 10 years ago I came across the one pictured, but no sooner had I got it up and running than I got a job offer out of the blue from Segway and I went to live in the US for 3 years. Over there I acquired a nicer lathe, albeit smaller, a CNC Bridgeport mill and a bunch of other stuff which I shipped back. Workshop space was at a premium so I got rid of the big lathe. A decision that I regret on the odd occasion. Although it cleaned up nicely, it had had a hard working life and the bed was heavily worn, so precise work had its problems.
Mar 5, 2017, 02:36 PM
Paul Jones

Doug,

Thank you for your link to your website. Lots of great information including the page with all the great links to other resources.

Regards,

Paul
Mar 5, 2017, 05:35 PM
Wmrra13

Hey Tony,

Coincidentally, I'm the process of restoring/setting up that same Asian 12x36 lathe. Where do you find parts for yours?

Also, I'm a bit out of the loop now but, I was club level road racer and subscriber to RRW&MT for many years and always enjoyed your articles. At least the parts I could understand....

Cheers,
Tyler
Mar 6, 2017, 04:46 AM
tonyfoale

Quote:

Originally Posted by Wmrra13

Hey Tony,

Coincidentally, I'm the process of restoring/setting up that same Asian 12x36 lathe. Where do you find parts for yours?

Tyler,

I haven't needed parts, but I guess that a Jet distributor could get anything necessary. Lathe parts don't change much over time. On the other hand there is much that couldn't be made at home.

Quote:

Originally Posted by Wmrra13

Also, I'm a bit out of the loop now but, I was club level road racer and subscriber to RRW&MT for many years and always enjoyed your articles. At least the parts I could understand....

Oh dear, I always try to make articles understandable, I obviously failed.
Mar 8, 2017, 12:00 PM
mr95gst

Wmrra13,
I am still a amateur with the foundry. Everything I have learned came from Youtube. I started out casting more complex parts with two part molds, but recent, all I have been casting is blank round or square stock. I have gotten so lazy with it that I just pack up some sand, cut a round plug out, and pour the aluminum in the top. When I did the backplate, I used a 1 gallon paint can to make the cavity. It was right around 7" in diameter.

Olderdan,
I like your powerfeed! I have been thinking about doing the same thing. The lathe only came with one set of gears. The SB 405 used a different gear pitch than most lathes so they are impossible to find. Lucky, the ratio I have is good for a slow clean finish pass. Without the gear set though, I can't power thread. Since I cannot thread, I have no reason not to convert to an adjustable motor driven leadscrew. At work, we have a Hardinge lathe that came with that feature from the factory. I love having the option to adjust the speed on the fly. Did you have to add something to the leadscrew at the foot of your bed? Mine stops even with the leadscrew bearing. I figured I would mount mine on the gear side since that end of the leadscrew lends itself well for mounting a pulley. What are you using to control the speed?
Mar 9, 2017, 03:27 PM
bigtrev8xl

Very nice job, I'm just about to start a total restoration of a 1940s horizontal mil.
How did you clean the the ways on the bed?
Thanks
Mar 10, 2017, 03:37 PM
mr95gst

I did most of the way cleanup by hand. I used scotch pads and soft bristled brushes. The bed portion was done with a pneumatic wire brush. The bed casting had the most flaky rust. It was one of the last pieces I did so I rushed through it. If you have significant rust, I would recommend electrolysis. You can make a quick setup with a battery charger, baking soda, and a scrap piece of steel. There are several write ups and videos on how to do it. I did all the other parts that way and it made clean up very easy. The rust disappears and it doesn't remove any extra metal. My bed was 4' long and I didn't have a big enough bin to submerge it in. If I wasn't in a hurry, I could have built a large wood box and lined it with plastic. In the long run, it probably would have saved me time to build a larger bin for electrolysis and it would have been a more thorough cleaning.
Mar 10, 2017, 04:26 PM
bigtrev8xl

Thanks for the reply.
I liked the way your bed looked really bright and clean.
I've got a 45 gallon tank set up for electrolysis rust removal, running off a 12v dumb battery charger, the arbor support, and motor mounting frame in there at the moment.
My table is 30" long, so it should go in my tank OK
I would really like to make a tank big enough to get the main body of the mill in, probably looking at best part of 100 gals
Electrolysis sure makes easy work of cleaning things up, and the real bonus is, it takes all the old paint off to :)
Cheers

Quote:

Originally Posted by mr95gst

I did most of the way cleanup by hand. I used scotch pads and soft bristled brushes. The bed portion was done with a pneumatic wire brush. The bed casting had the most flaky rust. It was one of the last pieces I did so I rushed through it. If you have significant rust, I would recommend electrolysis. You can make a quick setup with a battery charger, baking soda, and a scrap piece of steel. There are several write ups and videos on how to do it. I did all the other parts that way and it made clean up very easy. The rust disappears and it doesn't remove any extra metal. My bed was 4' long and I didn't have a big enough bin to submerge it in. If I wasn't in a hurry, I could have built a large wood box and lined it with plastic. In the long run, it probably would have saved me time to build a larger bin for electrolysis and it would have been a more thorough cleaning.
Mar 11, 2017, 12:49 PM
olderdan

1 Attachment(s)

Hi mr95gst.
This is the way that I attached a drive pulley to the leadscrew I have left this as a friction drive for the pulley for security, I think your lathe may have a ¾ bore in the mandrel to pass the leadscrew through to drill and tap and face the end.
I did face off 1/8 from the rear bracket by use of a stub mandrel which I did not think would be classed as vandalism to an old lathe.
The drive motor and gearbox is a 12v DC replacement for a Bentley golf cart new from fleabay for £25 and a PWM speed controller from the same source for £5 so not an expensive mod, a DPDT switch is also required for reversing.

Attachment 16951
My SB has a feed apron but I think you would be using your half nuts for this so would need a larger driven pulley than mine.
I am about to try some casting soon as my local factory closed and I have lost access to their scrap bins.
Regards
Olderdan
Mar 13, 2017, 05:28 PM
Carlos B

1 Attachment(s)

Very nice restoration. I like your flat belt solution. I have a South Bend 10K waiting for restoration. Mine is starting out a little cleaner but if I achieve even close to what you did with your 9" 405 I will be happy.I am sure I will be checking back here often once I start.

Attachment 16986

Carlos
Mar 14, 2017, 07:45 AM
mr95gst

Carlos, my kindred spirit! Nice machine. I am jealous of your gear box and power cross feed. These older lathes have nice shapes. Slap some paint on that thing and it will be a work of art. Be sure to keep us updated.