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Re: 2 Bearing Quill
Posted: Sun Apr 24, 2016 12:51 am
by reubenjames
I think that ends up just putting more stress on one of the bearings ultimately, or more stress on the drive sleeve, depending on the irregularity. I mean I understand the point, I just don't know if it gains you much in the end. It's one more wear part. I'd rather change out my drive sleeve than have to punch a bearing and replace. Though cost-wise I might not think that.
Re: 2 Bearing Quill
Posted: Sun Apr 24, 2016 1:07 am
by JPG
I tend to think that also. The bearings must be precisely aligned to gain a durable improvement.
I think side stress is better handled with multiple bearings.
Think large bowl turning or routing.
Re: 2 Bearing Quill
Posted: Sun Apr 24, 2016 4:54 am
by reubenjames
Very true, so I suppose usefulness would depend on the application, and its frequency, when weighing if it's a worthwhile thing. I just don't think they are an automatic "yes" despite the fact that I myself tend to put them in if opportunity presents itself. Thanks for indulging my tangent.
Re: 2 Bearing Quill
Posted: Sun Apr 24, 2016 11:19 am
by jjbuzard
I watched Shop Notes Replacing the quill and he says that if you insert the allen wrench and it only goes in 6" you have a 2 bearing quill, if it goes all the way in you have a 1 bearing quill, IF THAT IS true, my 1957 has a 2 bearing quill in it when I got it and the one in my 81 that I thought I replaced is a one bearing, and the used one in the 2 bearing quill box is a 2 bearing quill?????
Re: 2 Bearing Quill
Posted: Sun Apr 24, 2016 12:05 pm
by rcplaneguy
jjbuzard wrote:I watched Shop Notes Replacing the quill and he says that if you insert the allen wrench and it only goes in 6" you have a 2 bearing quill, if it goes all the way in you have a 1 bearing quill, IF THAT IS true, my 1957 has a 2 bearing quill in it when I got it and the one in my 81 that I thought I replaced is a one bearing, and the used one in the 2 bearing quill box is a 2 bearing quill?????
Remember the washer, you might be hitting that.
Re: 2 Bearing Quill
Posted: Sun Apr 24, 2016 12:13 pm
by jjbuzard
I think I got this figured out, according to the drawing below of the 1 bearing quill, there is a spacer disc about 4" in.

- 1 bearing quill.jpg (275.69 KiB) Viewed 2470 times
The 2 bearing quill doesn't have the spacer disc and the bearing is in about 6"

- 2 bearing quill.jpg (662.9 KiB) Viewed 2470 times
This is part of a multi page list from Shopsmith explaining the difference in model years I found in my Archives, here is the first page of that bulletin.

- Page 1.jpg (1.14 MiB) Viewed 2470 times
If anyone is interested I could convert the whole Bulletin to a pdf for down load.
Re: 2 Bearing Quill
Posted: Sun Apr 24, 2016 2:15 pm
by JPG
jjbuzard wrote:I think I got this figured out, according to the drawing below of the 1 bearing quill, there is a spacer disc about 4" in.
1 bearing quill.jpg
The 2 bearing quill doesn't have the spacer disc and the bearing is in about 6"
2 bearing quill.jpg
This is part of a multi page list from Shopsmith explaining the difference in model years I found in my Archives, here is the first page of that bulletin.
Page 1.jpg
If anyone is interested I could convert the whole Bulletin to a pdf for down load.
That would be good. It would fit in with DB5's pdfs.
The spacer typically resides at the internal end of the splines. 2" seems about right IIRC.
Re: 2 Bearing Quill
Posted: Mon Apr 25, 2016 1:45 am
by skou
I still can't figure out why they regressed from the
2 bearing quill.
The Model 10 always had the 2 bearings, but
early Mark series, not so much.
And, I've RARELY seen bad bearings on the
Model 10 stuff, after close to 70 years.
steve
Re: 2 Bearing Quill
Posted: Mon Apr 25, 2016 9:28 am
by everettdavis
Prior to 1962 Serial No. 37143 the Shopsmiths all had the Gilmer Drive, therefore unless you upgraded Poly-V which would have required the drive sleeve assembly and swap the sheave, and indeed updated it to a Poly-V belt at the time, you upgraded the other machine.
The quills and splines on the 1954 were different splines. If you didn't change it all out, you didn't likely upgrade the 1954 to the two bearing quill, unless someone else had previously converted it all to the Poly-V with the Single Bearing Quill already. That's the only way it would have fit.
Everett
Re: 2 Bearing Quill
Posted: Mon Apr 25, 2016 9:38 am
by everettdavis
skou wrote:I still can't figure out why they regressed from the
2 bearing quill.
The Model 10 always had the 2 bearings, but
early Mark series, not so much.
And, I've RARELY seen bad bearings on the
Model 10 stuff, after close to 70 years.
steve
I know the 10E / 10ER had far tighter tolerances on run-out. For example, today a Mark V single bearing quill can have .008 run-out and be in excellent condition. Upgrading to the two bearing can take it down to .002.
The original line failure to reject and send a 10E or 10ER back to manufacturing floor occurred if they found .0015 run out meaning that was too much to pass quality control. That said, the bearings on a 10E / 10ER were higher tolerance C1 bearings opposed to what is widely in use today.
Dusty posted something on this in a 2014 thread and likely in other places since. Here's that link if you want to read about bearings
http://www.shopsmith.com/ss_forum/viewt ... 66#p178566
So if you replace the 10E / 10ER bearings with greater tolerance bearings, the run out will go up over the C1 spec bearings that were OEM.
The C1-C5 specs have to do with axial and radial clearances within the bearings themselves. I am not going to get deep into the discussion on what is normal clearance vs the other specs, but post a graphic to help folks visualize what the differences are, not how much they vary per se. You can research deeper into that on you own if it interests you.

- Bearing Clearances.png (62.24 KiB) Viewed 2418 times
Everett