Can you adjust the head stock bushings on a southbend 16?

I have a 1926 16" south bend in the shop and noticed when I was puting a new chuck on I could take a bar and raise the spindle .030. How much "slop" does these bronze bushings suppost to have? Is there a way to adjust these?
Thanks
Chris

For the later 10" thru 24" lathes, the manual specs 0.0007" to 0.0015" movement if you lift on the spindle using a bar and a 75 lb load, so I would start from there. If the older SB's are similar to later ones, the bearing caps have shims, maybe "peel shims", to allow adjustment. If your lathe has many layers of paint or is dirty, they might be hard to see. I've not seen a 1926 SB, but generally the drill is you would pull the bearing cap bolts, slide out the shim, insert a thinner one (or if its a laminated shim, peel a layer away), replace the shims and retighten the caps. If you're doing this I would pull the caps, lift the spindle and replace the felt oilers at the same time, they probably need it.

Jeff

I wonder if your all out of shims if you can surface grind the top hull down a little. Or should it be new bronze bushing made? I figure if you made new bushings you would need to regrind the spindle to be true. What are your thoughts?
Chris

Chris:

Given that yours is a 1926, it does not have felt oilers.

Most of the wear will be on the bottom half. If there are no shims to remove, you could machine off 30 thou off the top ends of the bottom bearing which will allow take up of the 30 thou you now measure. This might require a thou or two of shim to be place between the bearing halves.

Then start shimming between the bottom bearing and the head stock to bring the front end of the spindle up so that the axis of the spindle is parallel with the bed. This gap in which you will be shimming is not uniform but crescent shaped so that you will need shims of varying length to fill this space.

While you are into this exercise, you should also check the the spindle bearing at the back end of the tail stock as that may also need work.

Jim C.

I guess all this play could contribute to the bam, bam, bam, I get when I try to take an real heavy cut. I am going out to the shop and will report back latter tonight on what I found.
Chris

I got it down to .007 slop, I wonder it thats good enough, or should I machine it down?
Chris

Keep going. You might even want to go further than .007 and add an adjustable peel shim stack ("laminated shims" at McMaster Carr), so you wont have to go through all of this in the future.

Jeff

Chris:

Keep it simple ! Use only one thread for a given problem, not three !! That way everyone will be reading from the same sheet of music !!!

Re: 30 thou spindle movement.

Jim C.