South Bend Lathe Stead Rest Mod

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When I bought my big old South Bend last year, one of the reasons I wanted it was because of its long bed. The lathe is a 15 or 16" swing, with what's called an 8' bed, although in reality the center to center distance is about 6 feet. A lathe of this size allows for some interesting projects. But to chuck up anything of any real length, you need a steady rest. A steady rest is also required to cut an inside snap ring groove in a motor casing. With my new 3.5" motor project and the Prelude rocket, I decided it was time to get the lathe ready for a big project.

I wanted to do a couple of things on the lathe. First, I wanted to cut a groove for a bulkhead snap ring. Second, I wanted to sand the body tubes on the lathe. Both of which would require a steady rest, which I had. But.

Here's the picture of the steady rest the way I received it. Notice the actual pads the turned object rests on. They are steel, which didn't seem like a good idea for an aluminum motor casing. And really not a good idea for a fiberglass or PVC tube to ride on.

So I decided to add some bearings. Now the problem was the steady rest only had an inside diameter of 5", I couldn't just add bearings to the ends of the guides that were there or I wouldn't have the diameter I needed. So I had to get a little creative.

Here is one of the bearings I picked up. I couldn't find a bearing in the size I wanted with a smaller inside diameter. So I had to make bushings to go inside the bearing. The bushings were turned from 3/4" stock down to the desired outside diameter. Then I bored them out to 3/8" to accommodate a bolt.

Here is one of the bearing holders. I found some 1.25" square tube and cut it to length. Then I had to slot one side for the adjustment. The slotting would have been a lot easier if I had a mill, but I don't. So I drilled out a series of holes, then used a small angle grinder, finishing with a hand file.

The other end was drilled out to 3/8" to bolt on the bearing.


The last thing I had to do to the holder was to weld on a small tab for the adjustment bolt to push against.

Here is one of the bearings with the bushing and washers on it, ready to be bolted to the holder.


Here's the set bolted up to the holders.

Here's the end result. If you look at the top bearing and holder, you can see the bolt that goes through the holder, then through the frame to secure the bearing holder in place.

This arrangement allows full use of the 5" inside diameter of the steady rest. It looks like it should work. I'll find out when I get the Prelude rocket motor casing next week.

Here's a picture of the steady rest in use. I'm sanding one of the Prelude body tubes. As I expected, this will make sanding body tubes a breeze, and save me hours of work. I should have removed the tail stock, in the picture it almost looks like the tail stock is being used. It isn't, I was just too lazy to take it off, the drill chuck is in the end of the tube.