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Rif
02-06-2008, 11:45 AM
Hello,

I am in the process of putting my 13 Inch South Bend Lathe back together and I am in need of a set of thrust bearings, for both the spindle and the cross slide lead screw. I just searched through both MSC and McMaster looking for these bearings and have not been successful. So, I searched through the PM board and found that they are proprietary bearings and, in a 2003 posting, it was reported that the spindle thrust bearings cost $160! It was also mentioned that they didn't use standard bearing sizes so that you had to go to the vendor for parts. :rolleyes:

So, I am thinking about making a set of plain bronze bearings and setting them up similar to the way the thrust bearing on my ancient Pratt & Whitney is oiled. Does anyone have any advice or opinion on this solution to otherwise paying an outrageous price for bearings?

Thanks,

Brian

garyphansen
02-06-2008, 12:23 PM
I replace the fiber washer in my South Bend 9" lathe with a radial needle bearning and two harden washers. It would seem to me that the cridtical dimentions would be the I.D., O.D., and the thickness of the bearning and the two washers. As long and the I.D. is the maxium size or smaller all is good. The thickness has some laidtude in the take up nut. So, as long as the O.D. is larger than the shaft you could make a bushing to take up the difference.

I am sure your idea would work, only just not quite as well.

When I made this modification< I was able to adjust all right-left play out of the spindel. Gary P. Hansen

Rif
02-06-2008, 02:01 PM
I replace the fiber washer in my South Bend 9" lathe with a radial needle bearning and two harden washers. It would seem to me that the cridtical dimentions would be the I.D., O.D., and the thickness of the bearning and the two washers. As long and the I.D. is the maxium size or smaller all is good. The thickness has some laidtude in the take up nut. So, as long as the O.D. is larger than the shaft you could make a bushing to take up the difference.

I am sure your idea would work, only just not quite as well.

When I made this modification< I was able to adjust all right-left play out of the spindel. Gary P. Hansen

The South Bend 9" used a fiber washer as a thrust bearing? Very interesting. The 13" used two ball bearing thrust bearings, one on each side of the left-hand spindle bearing. I suppose radial needle bearings would work, as well. But, I can't find either in the size I need. I didn't call the company that bought South Bend because I already saw what the price was, in 2003.

Specifically, what I am thinking of is using 3 "washers" as bearings on each side of the spindle, to replace the ball bearings. The "washers" would be arranged as steel, bronze, steel. The inner steel washer would have a groove in it about half way between the inside and outside diameter. This groove would be an oil groove to ensure that oil is between this washer and the bronze and the washer would be installed with the groove facing the bronze washer. This washer would also have a number of holes drilled in it to allow oil to flow from the spindle side to the oil groove. The next washer would be bronze and may have a blind hole in it for a locater pin with the outside washer. The outer washer would be a steel backer for the bronze washer and may have a locater pin installed to keep the bronze washer from rotating against it. Of course, these items will have to be shop-made.

Regards,

Brian

lazlo
02-06-2008, 02:08 PM
Brian,

Can you get an off-the-shelf, three-piece thrust bearing and machine it to fit?

Surely the inner diameter is standard, and INA sells a complete compliment of ball- and needle- thrust bearings in inch sizes.
Just make sure you have enough meat on the OD to turn it down to whatever size you need.

The thrust washers are hardened, so you'll probably want to use a carbide or cermet insert to hard-turn it, unless you have a toolpost grinder...

Cheers,

Robert

garyphansen
02-06-2008, 02:19 PM
Rif: If you were to ask for part numbers for a bearing and washers that would work on the South Bend forum on the PM site, I am sure that some one would have an answer for you. Gary P. Hansen

wierdscience
02-06-2008, 02:21 PM
Aetna bearings does ball thrust bearings as does INA.I have both catalogs at work and about four more sources for them if you want to post the dimensions you need I can look see if there is a substitute.

http://www.aetnabearing.com/aetna_products.htm

http://www.inausa.com/prg_download/

You could also substitute need thrust bearings if you can find the right OD/ID.

Rif
02-06-2008, 02:33 PM
Brian,

Can you get an off-the-shelf, three-piece thrust bearing and machine it to fit?

Surely the inner diameter is standard, and INA sells a complete compliment of ball- and needle- thrust bearings in inch sizes.
Just make sure you have enough meat on the OD to turn it down to whatever size you need.

The thrust washers are hardened, so you'll probably want to use a carbide or cermet insert to hard-turn it, unless you have a toolpost grinder...

Cheers,

Robert

I *was* hoping to get something off-the-shelf. The inside diameter is 1.875, the outside diameter is about 2.575, and the thickness is 0.375. I am just not will to pay over $360 for it.

I just checked McMaster-Carr for the bronze thrust bearings and found some that I can machine down to size. While there, I also found some stainless steel washers (5 pack) that I can also machine down to size. So, I'll attempt to make the bearings out of the washers and bronze bearings. (The bronze bearings are basically bronze washers.)

It should be interesting to machine the washers to size. I was thinking about ordering a 2" length of 2 3/4" bronze to machine....at about $40. So, I just saved close to $20 by doing it this way. That is not a problem as I will still be over $300 ahead of the game. :)

Regards,

Brian

Rif
02-06-2008, 02:45 PM
Rif: If you were to ask for part numbers for a bearing and washers that would work on the South Bend forum on the PM site, I am sure that some one would have an answer for you. Gary P. Hansen

I searched that site and found the information about the price of the bearings. Once I saw the price I didn't bother to inquire about the part number. That was when I checked with MSC and McMaster and saw that the cage assemblies, close to the right size, cost less than $4.00 each. The washers cost either 2.03 or 10.62, each, depending upon thickness. That was when I decided that even $100 is too much for a $25 bearing.

Brian

Rif
02-06-2008, 02:47 PM
Aetna bearings does ball thrust bearings as does INA.I have both catalogs at work and about four more sources for them if you want to post the dimensions you need I can look see if there is a substitute.

http://www.aetnabearing.com/aetna_products.htm

http://www.inausa.com/prg_download/

You could also substitute need thrust bearings if you can find the right OD/ID.


Thanks. I just checked both sites. The second has an online catalog and they don't have the right sizes, either.

From what I read, on the PM site, I believe the bearing sizes were specially made for South Bend.

Brian

lazlo
02-06-2008, 02:52 PM
I *was* hoping to get something off-the-shelf. The inside diameter is 1.875, the outside diameter is about 2.575, and the thickness is 0.375.

There's an industry-standard ball thrust bearing that's close: the EW1-7/8: 1.875" ID x 2.750" OD x 0.625" thick.

With the bearing being so thin, is that a needle thrust bearing?

Rif
02-06-2008, 03:05 PM
There's an industry-standard ball thrust bearing that's close: the EW1-7/8: 1.875" ID x 2.750" OD x 0.625" thick.

With the bearing being so thin, is that a needle thrust bearing?

The original (I am assuming it was original.) thrust bearings were ball....with very tiny balls. I would try a needle thrust bearing, if I could find one. I think an outside diameter greater than 2.575 would work...just not too much greater. 2.750 would probably be acceptable. Unfortunately, that bearing is way too thick.

Regards,

Brian

pcarpenter
02-06-2008, 04:31 PM
Either that's a typo (perhaps should be .0625"?) or its not thin at all. Likely its the former and could work for you as most thrust bearings are not 5/8" thick.

Edit-- do check the load bearing abilities. I recall noting when I was looking for a needle-type for a vise thrust bearing that some of the ball types were not designed for much load. Also, some are speed limited....they are not a packed or oil fed bearing after all.

Paul

lazlo
02-06-2008, 04:53 PM
Either that's a typo (perhaps should be .0625"?) or its not thin at all. Likely its the former and could work for you as most thrust bearings are not 5/8" thick.

No, that's not a typo -- it's a ball thrust bearing. Most ball thrust bearings are that thick (or thicker).

Are you thinking of needle thrust bearings, which are much thinner?