Full tear down and Rebuild of a 10EE Round Dial

[GrantGunderson]

Here are the various aligment marks in relationship to each other. Notice the "V" that was top center when I pulled the spindle from the headstock is close but not aligned to the factory bearing alignment marks. There is another short aligment mark on the front that does align with the "V". I also found a "T" on the backside of the Spindle flange, so guessing this is a fitters mark from hand fitting the front spindle retainer to it.

On the reverse side of the spindle is a paint splotch... looks like the original paint from the inside of the head stock and another fitters mark.

Here is the alignment mark for the inner race. The outer race mark, according to my research is the high point for the bearing. One of my Front Duplex bearings had a "12XX" on it. This matches the rear spindle bearing and I believe that is the amount of eccentricity the bearing has, so the factory installed a full match set of Front spindle bearings and rear spindle bearings. However, I have reason to believe one of my Front Duplex bearings was replaced at some point at has a "13XX" so seems like they tried to match it as close as possible..... Interesting.
The front Spindle bearing retainer plate, had what looks like a ton of extra gasket compound that was blocking most of the front oil labyrinth seal and ports. So Glad I took it apart to clean it.

 

[Cal Haines]

Was any force needed to remove the bearings from the spindle?

 

[grounding]

Was any force needed to remove the bearings from the spindle?

Cal, the rear front spindle bearing came off easy for me, the front front spindle bearing needed some effort. Interesting to see what Grant says.

 

[GrantGunderson]

The rear bearing in the duplex stack I was able to just lift right off. The front bower required a few taps from the palm of my hand on the front retainer. Some cried from the gasket has made its way between the flange and retainer. So that might have had something to do with it. All of the bearing stack components seem to be ground very precise.

 

[rakort]

I'm surprised actually that we can remove these AC bearings from the spindle with minimal intervention, this doesn't sound OK. Certainly there is a balancing act between clearance, zero/minimal interference and race distortion causing interference. I spent some time in the "books" for spindle restoration and bearings and yes things are/should be precise. There is an over whelming amount of information out there on precise spindle restorations that I digested (some of it) when I restored my milling machine spindle. Presses should not be involved unless its for disassembly and there after disposal of bearings. Normally a mild temperature difference +/- 100F should be enough to induce the temporary clearance to assemble precision bearings on a spindle. I chilled my spindle outside (it was winter) and heated slightly the bearings in an oven and they dropped right on. There after I could not get them to move by hand. If all else fails there is Loctite! The other hot topic related to this is AC bearing pre load. The "simple" topic of how to preload angular contact bearings is another HUGE topic. This is one of the reasons I cringe when I see that folks have beaten on the main spindle retaining nut to try and improve something? Search Angular contact spindle bearings and be prepared to.....

Brian

 

[GrantGunderson]

I found it interesting that the ND literature just states that the bindings and bearing spacers are ground to obtain proper preload, but no where is anything stated about what the correct torque on the bearing lock nut is.

I’m thinking I’ll reach out to monarch and ask, I need to order some parts anyways.

 

[rakort]

I found it interesting that the ND literature just states that the bindings and bearing spacers are ground to obtain proper preload, but no where is anything stated about what the correct torque on the bearing lock nut is.

I’m thinking I’ll reach out to monarch and ask, I need to order some parts anyways.

Well now you are on to it! There is no correct torque, crank it down as tight as you like...ish and give it some more it won't matter. The AC bearing preload is not established by the torque of the nut at all. The preload is established by the uber precision grinding of the spacers (if spacers are involved in the setup) and/or grinding of the faces of the races.

I haven't figured all this out yet, but if you have inner and outer race spacers (I think a 10ee does) in theory they need to be matched (ground) under a preload in harmony with the bearings. We don't have the capability to do that unfortunately.

I have no answer for you there.

I also know on the market are universally matched AC bearings. In theory you can combine 2 separate universally matched AC bearings and end up with good results as long as spacers are not involved or the spacers are match ground.

Like I said.....there is a lot involved it precision spindle AC bearings. A lot more than I know or could even articulate.

For my mill spindle (I left well enough alone with the 10ee spindle) I sourced some universally matched bearings and rolled the dice. So far so good with them.

Brian

 

[rakort]

https://www.skf.com/us/products/rolling-bearings/ball-bearings/angular-contact-ball-bearings

 

[GrantGunderson]

Well now you are on to it! There is no correct torque, crank it down as tight as you like...ish and give it some more it won't matter. The AC bearing preload is not established by the torque of the nut at all. The preload is established by the uber precision grinding of the spacers (if spacers are involved in the setup) and/or grinding of the faces of the races.

I haven't figured all this out yet, but if you have inner and outer race spacers (I think a 10ee does) in theory they need to be matched (ground) under a preload in harmony with the bearings. We don't have the capability to do that unfortunately.

I have no answer for you there.

I also know on the market are universally matched AC bearings. In theory you can combine 2 separate universally matched AC bearings and end up with good results as long as spacers are not involved or the spacers are match ground.

Like I said.....there is a lot involved it precision spindle AC bearings. A lot more than I know or could even articulate.

For my mill spindle (I left well enough alone with the 10ee spindle) I sourced some universally matched bearings and rolled the dice. So far so good with them.

Brian

That goes right along with what I found researching it as well. I did find some modern replacements for the Front Duplex set, but have not found any with the flange, and they are all $2K plus, and are special order.

I did a bit of a deep dive into the bearings for my 10EE and complied a pretty complete list of all of them, minus the Cross Feed, compound and tail stock thrust bearings. Here is a thread with that list. I included an google dock link to an Excel file with them as well that also includes modern replacements for many of them and my notes. I was able to order all new bearings for my machine, except for the Front Spindle Duplex set for under $800

 

[rakort]

Someone said that a place called LA Bearing (if I recall correctly) had some 10EE spindle bearings.

 

[GrantGunderson]

Someone said that a place called LA Bearing (if I recall correctly) had some 10EE spindle bearings.

I’ll see if I can find them.

I was chatting about the spindle bearings with my Dad the other night and he then sent me this email.

“Grant talking about bearings made me think about when I designing an inspection device for use in a hot cell where the the heat and extreme radiation existed, such as the bearing grease could not stand the environment. I went with a sleeve bearing made of Graphite. the results were such as no break downs occurred. DAD”

Guess we have it easy in the search for 10EE bearing replacements.

 

[daryl bane]

If LA Bearing (Los Angeles) is still around, and if Robert (Bob, I think that is his name) is still with us, that would be the first place I would check. He had made up a batch of matched EE spindle bearing sets back in the day and his price (at the time was very reasonable), And accuracy was superb, as good or better than factory. Also he was a wellspring of knowledge on all the bearings used in the EE.

 

[GrantGunderson]

As far as I can tell via Google LA bearing is no longer around.

 

[daryl bane]

See this is what happiness when you get old and your memory goes. The Co. Is General Bearings in LA, CA. 323 588-2101. And they are very much still is business. Talk to Bob, if he is still there.

 

[GrantGunderson]

Wow. Awesome! I’ll give him a call

 

[daryl bane]

Uh oh, I just saw that they were recently "permanently closed" on Google. If true, thats a bitch. Their website came up, and I "assumed" they were still in business. Everything going to hell nowadays. Sorry to get your hopes up on a now bum lead.

 

[GrantGunderson]

Ok they are open. Modern replacement as I had found is 7212. They do not have any of the originals left. He has both Nachi and one other brand in stock. $600 ~ $700 a set. Mine still appear good, so might hold off on replacing until I can put a test bar in the spindle.

 

[rakort]

See this is what happiness when you get old and your memory goes. The Co. Is General Bearings in LA, CA. 323 588-2101. And they are very much still is business. Talk to Bob, if he is still there.

Ahh yes, General Bearing, thanks Daryl!

 

[Cal Haines]

Ok they are open. Modern replacement as I had found is 7212.

Modern replacement for which bearing?

 

[GrantGunderson]

Modern replacement for which bearing?

7212 Is the front Duplex set for the spindle. They need to be ordered either as a matched DB set, or the more modern method is purchasing separately with the bearings marked as DU, which basically stands for Duplex universal. Those are ground and designed to be used in any of the Duplex configurations.
It seems most of the ones that will have a flange, will be a 7212DB

You can get them now in ABEC 5, 7 or even 9, depending on how much you want to spend. The challenge is finding them with the flange for the front bearing. That is typically signified by either an N or NR, but there are other codes for it as well.... Still doing more research, but from what I have concluded, especially after talking to the guys at General bearing today, getting modern replacements that are a direct fit is no issue.