South Bend 13 spindle bearing caps

A couple of years ago I bought a south bend 13. It wasn't very expensive and at the time I didn't notice that the front spindle bearing cap was a shop made replacement. I've used it that way for a while but noticed that there was too much play (around .012) in the spindle. When I took the shop made cap off there were no shims to remove. Without thinking it all the way through, I bought some bearing caps thinking it would be an easy fix. I am now thinking that the headstock and bearing caps must be machined together. While the new caps go on ok, the alignment pins are not perfectly aligned and it locks the spindle after just a little tightening while the cap is still 1/8 inch up on both sides. I am wondering if removing the alignment pins is a viable option. The existing shop made cap does not have any pins. Any ideas?.

Thanks,
Paul

There were two different sizes of spindle for the 13, with each with a different OD. Perhaps you got the wrong ones? If not, then I would try removing the pins, just to see.

allan

Spindle is the larger of the two sizes and appears to the eye to be correct.

Thanks,
Paul

The pins appear to go all the way through the bearing cap and are a tight press fit. I will try to press them out.

Thanks,
Paul

each bearing cap is line board in place on the headstock. Just like the bearing caps on a engine crankshaft. If you swap them, they will be misaligned. Only on a very rare occasion will two be compatible with each other. It is never a good practice to swap them. In your case you might get lucky with removing the alignment pin. But chances are you can go through 1000 bearing caps, And not find one that will fit correctly. If this one doesn't work, you would be better off replacing the headstock.

I hope you can get it to work.

Stay safe and have fun.

Joe.

I pressed the alignment pins out. I think that did the trick. I haven't finished shimming but I was able to tighten the bolts to the point where there is little to no up and down spindle movement with the spindle spinning freely. There is room to add shims which I will do tomorrow.

Thanks,
Paul

Another thought, once every thing is bolted down tight and working I might run a end mill the size of the pin down the alignment pin holes so that I might be able to reinstall the alignment pins by cutting the holes in the headstock to realign them. They would no longer be perfectly round but the pins would fit. They only protrude maybe 3/8 inch and the end is tapered.

The alignment pins don't go all the way through the caps. The end is plugged with lead.

If the shop made cap (caps) look Ok and alignment pins line up I likely would stay with them and skim the bottom to get down to where a .015 cap shim set would fit under and a blue in fit over the ,015s.

For The repair shims likely I would forget about the mis -line pins, set .015 caps shims in the shim position then scrape the cap to make a blue in fit to be zero to .002 with the .015 cap shims on place holding with the bolts.

Then I would put in .002 at the bearing clearance, draw the cap screws to even and just snug and just locking spindle and re-drill and ream a couple new pin holes through the cap into the base.

Trying to catch the old pin hole that may not even be straight to make a .001 location would be difficult.

*Starting with .015 may not be best so a South Bend guy should chime in and say what would be best for making a cap fit. Perhaps .025 would be the better choice?

You want a blue in fit so up-and-down and in-and-out are both a blue in fit.

How do you deal with the bearing expander when checking the blue in fit?

I think I would rather not use the shop made bearing cap because it's a bit oversized and interferes with the bull gear engagement pin. The shop made cap has no alignment pins and is not drilled for them.

Thanks,
Paul

So far so good, I used the eBay purchased replacement cap. I shimmed it until I had approximately .001 movement using a one foot bar. Then I very carefully ran a 5/16 end mill down each alignment pin hole with the cap firmly bolted in place, there was very little metal removed, but I was able to install the pins and cap them off with lead. In the process of having the spindle out, I replaced the felt oiler wicks and cleaned out and refilled the oil. I ran the lathe for around a half hour and it worked good with no heat felt on the replaced cap...