Upgrading Thrust bearing

[timpet98]

Hi, I've got a 1936 Atlas/Craftsman 12". That year was the last before they began to offer the Timken bearings so mine are Babbitt. I have been running into issues with the bearings when I use carbide insert tooling. I do not think that it is a lubrication problem, because I am using the recommended spindle oil, and lubricating at a minimum at the beginning of each day that I use it. When using carbide tooling the axial forces seem to be much higher, and the "thrust bearing" gets all of the oil pushed out and has completely locked up and galled on me once. After that happened I have been careful to constantly add oil to the rear bearing. I'm taking a 20thou on the dial cuts about 12" long on 1144 stressproof which is free machining. I have to add oil every 3-4 passes which seems like quite a lot especially in comparison to when cutting with HSS where I only have re-lubricate maybe once or twice over like 4-5 hours of run time.

I was thinking about replacing the "thrust bearing" collar with some sort of ball/roller thrust bearing. I keep saying "thrust bearing" because it is just a steel ring that is butted up against the step in the spindle and bears on the edge of the Babbitt bearing. I already have a visible amount of end play in the spindle because when I had it tighter I was having problems constantly. I was wondering if anyone had retro-fitted their Babbitt lathe to have a thrust bearing of some sort like on South Bend lathes.

The pictures I have attached are in order as follows: my lathe's thrust bearing (its black), the dimensions of the ring, a page from the South Bend Catalog detailing how their bearings worked.

From what I can tell I could use a ball thrust bearing or a roller thrust bearing. I was wondering what the advantages and disadvantages of either are. Let me know what you guys think.

 

[wa5cab]

Welcome aboard. I think that you have the earliest 12" Craftsman lathe that I have seen. What is the serial number? It should be stamped into the front way at the right end of the bed. Your machine would appear from you photo to be a 101.07360 as it does not have the back gears. We do not have any parts lists on any of the 101.0736x family. However, nearly 10 years ago, I downloaded all of the Atlas lathe parts lists that were still available at that time on Sears Parts Direct. That included all of the 101.0736x. 101.0738x and 101.0740x lists (12 total) and I wrote some dBase code that makes it fairly easy to find things in the lists.

Forget about South Bend. Your main problem, at least according to the Sears parts lists, is that someone has removed the 10D-61 ball thrust bearing and replaced it with a steel sleeve. There is also or should be a short pin in the spindle that keeps the thrust bearing from spinning on the spindle. It's part number is 9-116 but it was left off of the parts lists. I am trying to track down the part number but the smaller diameter sleeve to the right of where the 10D-61 should be is the spacer in lieu of the small spindle back gear that your machine does not have. There are some other differences between yours and the 101.07380 that I am not yet clear on. Take another photo of the right end of the headstock.

 

[graham-xrf]

Aw ..he was thinking to put a bearing back in there anyway. Nothing wrong in making the same design decision as the guys at South Bend.

 

[wa5cab]

Why reinvent the wheel? We know that the 10D-61 worked well. I am still curious to see what the other end of the 4-step spindle pulley looks like and how it is held in place.

 

[timpet98]

I'm not sure exactly what the "10D-61 ball thrust bearing" but if I'm understanding this correctly it sounds like the same thing that the south bend had. A ball thrust bearing in front of the rear Babbitt spindle. The stamping reads L5-224. I would like to keep it as original as possible, within reason, it has a few problems that I'm trying to find creative ways around in order to keep as much as l can original. If the original bearing is something that I can easily obtain at a relatively low price I would love to find one. I'm a 22 year old college student so my budget isn't huge, but since I know the history of my lathe all the way back to the original date of purchase I try my best to preserve it.

My Grandpa purchased it in the 80's from the widow of his long time neighbor who originally purchased it in 1936. My Grandpa never got around to setting it up and running it, so while I'm the third owner, I feel extraordinarily lucky to be the second person to ever operate this piece of history. The previous owner made some modifications. Primarily adding a plunger type feed selector like is seen on the Craftsman lathes sold the very next year. I'm sure that probably drove him nuts at the time to see such a drastic improvement the year after his purchase.

The other major problem is that the cross slide/swivel for the compound, was made of ZAMAK and is of a completely different design. I am looking to replace that part as well with a modified version of the new cast iron one. I could replace the whole compound assembly and it would be VASTLY easier, but again I want to keep things original. The first picture that I attached is of both cross slides, with the cast iron one coming from my 7"-x-y positioning table that I bought to go on my 1942ish Craftsman (Atlas) drill press. I'm not willing to sacrifice that one, but I'm trying to track one down to modify. The ZAMAK one has a couple of problems, obviously 3 gib adjustment screws and 1" less bearing surface isn't preferable. But the MAJOR problem is that unfortunately I sort of "broke" it. I say that in quotes because I can still use the lathe, but after I took this picture I set the compound to 29 for threading, and then likely over tightened the nuts, pulling the T-nuts up into the soft zinc and raised a burr in the track around the bolts. Now they are stuck and I cannot move my compound off of 29.

I would like to track down another cross slide, grab it in a 4 jaw and turn down the round dovetail feature, and then trapan out a slot, and subsequently use an extraordinarily odd left and right hand grooving tool to turn a t-slot into the cast iron compound. All of the measurements should work out, I know that the slide does slide on the dove tail, from when I used the table from 7"-x-y thing to horizontal bore holes in some flat plate.

The cone pulley on the spindle is just held in place with a set screw, and this is sometimes problematic (comes loose from vibration/rarely on heavy cuts). I know that on back gear models that the set screw SHOULD NOT be tightened, but there is no other way for my lathe to work. I would like to come up with some sort of sleeve with a key-way in the bore and a pair of pins going into the recesses in the cone pulley, similar to when direct drive is engaged on a back gear lathe. The pins would not need to move in and out because it would always be in direct drive. I would need a slug of probably aluminum about 4-3/4" diameter and 1-1/2" long but with the local place I but drops at being closed right now. I'm not going to get to it for a while because shelling out the price of getting it cut off from somewhere like onlinemetals and shipped isn't really an option for me.

Could you please upload a copy of the parts manual that you have for the Babbitt bearing lathe? I haven't been able to find anything but the Timken version on Vintage Machinery, or even just a screenshot of the page showing the spindle. I'm not quite understanding what the arrangement of bearings/spacers on my spindle should look like. I know this lathe never had back gears, because the cone pulley has the index pin holes and the pin itself is too long to fit with a back gear. Despite this the rear is still milled flat and has the 4 taped and 2 reamed holes to mount the counter shaft.

Let me know if you want pics of anything else I'd be glad to upload them, here are some more of the headstock.

Sorry for the ramble, just a lot of things going on with my lathe and lots of questions I have been dieing to find answers for.

.... one last thing just came to mind, what can I do to retrofit some way wipers onto saddle, there aren't any and I have to take the whole thing off constantly because small dust like chips find their way under and I have to take the saddle off completely to clean it out. Feeling the grit under their is like fingers on the chalk board to me.

 

[timpet98]

I just walked over and stared at my lathe for a minute trying to remember what it looked like when I had the spindle all the way apart after the first time it seized, and I am fairly sure there was a drive pin under that collar. Unless I am remembering when I just helped my friend out by taking his 1942 Timken headstock apart. If that pin is only on the Babbitt versions then it is there.

 

[wa5cab]

This was written several hours ago but I got interrupted. If any of it has already been answered or is outdated, just disregard.

OK. I'll answer your last question first. The babbit bearing spindle # 10-31 is different from the Timken spindle # 10-31T. The first obvious difference is that the 10-31 has the hole for the 10-116 pin that makes part of the 10D-61 Thrust Bearing spin with the spindle. 10-31T among other things does not have the hole.

Finding an original 10D-61 may not be easy. However, the same bearing was used in all of the Atlas babbit bearing 10" and Craftsman 12" lathes up through 1945 when production ceased. So it shouldn't be impossible to find someone parting out one of the lathes. The original spec 10D-61 is no longer made and the replacement that Clausing has or had seems to be a little larger or something. But that shouldn't cause you any problems as as you have said and the photo shows that there is plenty of room to slide the spindle step pulley toward the tailstock in order to assemble everything. However, like the Timken bearings in Class 3 tolerance, it ain't cheap.

I will check in Downloads for what would be the nearest parts manual to the unavailable one on your machine. However, as you may have already discovered, access to Downloads requires being a site Donor. The least expensive dollar amount is $10.00 good for one year. There are higher levels but as far as Downloads is concerned, all levels have the same Downloads access. The higher donor levels gain access to other things. I think that there is a chart showing all of that if you click on the Donations tab in the top main tool bar. So you need to factor that into your plans.

 

[timpet98]

The space for the bearing as it is is 3/8 in width and the same ID size that McMaster has is 5/8 width. Is that 5/8 the same size as new bearing offered by Clausing? Either way I anticipate that being a problem, not because if the cone pulley, but because of the amount of space left on the other side of the bearing where the gear for the change gears is, and the spindle preload nut. It might not matter, but I'd have to take a look tomorrow and see how much space is back there. Also not sure of how the bearings would take being shifted along the spindle shaft, because where they are now are much more polished than the rest, again ill have to look at it tomorrow.

 

[wa5cab]

Well, no one else spoke up, which sorta surprises me. But...

I have confirmed unfortunately that we do not have a parts list on any of the 101.07306x models nor on any of the less easily identifiable 10" ones that do not have back gears. The closest thing that we do have, besides the Sears Parts Direct lists without any drawings and not available online, is an early flat parts list on the 101.07381

 

[wa5cab]

Oops, I must not have updated the browser screen.

At least two people have said that they had trouble installing the currently available one from Clausing. However, I didn't have the impression that it was as much as 1/4" wider.

However, there is a solution in your case IFF you have decided not to try to acquire the back gear parts. And that is to either cut off the sleeve spacer that is between the thrust bearing and the cone pulley or to make a shorter one.

I would imagine that if you call Clausing, and ask for Tech Support instead of sales that they would be willing to go and fetch one of them, measure it, and tell you what the thickness is. And the price. What does the one from McMaster cost?