mid-'50s shopsmith disassembling and cleaning -- help

[JPG]

EDWARD: If I recall correctly when Bill Mayo recommended a C1 bearing, it was for the quill(single bearing). This bearing is INSIDE the quill. I was under the impression you were trying to replace the gilmer drive shaft bearings.

[edward]

Right. This is for a single-bearing quill. My supplier should have done a lot of things that he didn't. Instead of looking it up, he measured it and compared the measurement to the old one. So, finally, I asked him to look up the right size and he said they have it, but in C3 only. According to Bill, there's no C1 for the 6202 version. But there is for the Fafnir.

[JPG]

Right. This is for a single-bearing quill. My supplier should have done a lot of things that he didn't. Instead of looking it up, he measured it and compared the measurement to the old one. So, finally, I asked him to look up the right size and he said they have it, but in C3 only. According to Bill, there's no C1 for the 6202 version. But there is for the Fafnir.

Let's be very explicit here:

The drive shaft bearings are ???? ?? ?? ????
The single quill bearing is ???? ?? ?? ????
The control/idler shaft bearing is ???? ?? ?? ????
The Motor bearings are ???? ?? ?? ????

We have been throwing part numbers around and I for one am NOT at this point sure which is which.

[tdubnik]

A C1 bearing should not be required for anything on a Shopsmith. I worked for SKF Bearings for over 25 years. We supplied bearings for everything from electric motors to automotive to medical equipment. The ONLY industry we routinely had to supply C1 bearings was the aircraft industry. When we ground and polished the bearing races and balls; the tolerances were measured to within +/- .0003 (3 tenthousandths) of an inch.

The normal bearings were C3 and they went into everything. We supplied GE, A.O. Smith, Reliance Electric, Baldor and several other motor manufacturers. We supplied Black & Decker, Makita, and other electric tool makers. We supplied GM, Ford, Chrysler, Toyota and many other support companies in the automotive field. ALL of these companies used C3 bearings. The only difference was that the electric motor manufacturers required the bearings to pass an extra "noise" test.

A good brand C3 bearing should work anywhere in the Shopsmith.

[beeg]

Right. This is for a single-bearing quill. My supplier should have done a lot of things that he didn't. Instead of looking it up, he measured it and compared the measurement to the old one. So, finally, I asked him to look up the right size and he said they have it, but in C3 only. According to Bill, there's no C1 for the 6202 version. But there is for the Fafnir.

So if ya had sent it to Bill M. you'd have it back by now and KNOW it was right.

[JPG]

[quote="tdubnik"]A C1 bearing should not be required for anything on a Shopsmith. I worked for SKF Bearings for over 25 years. We supplied bearings for everything from electric motors to automotive to medical equipment. The ONLY industry we routinely had to supply C1 bearings was the aircraft industry. When we ground and polished the bearing races and balls]

Methinks this all boils down to: How long should it last. How much runout can you tolerate over that period of time. What temperatures will it be subjected to. How quiet it needs to be. How reliable(fail safe[things which may fall from the sky]) does it have to be.

I am sure that if motor manufacturers DID use 'tighter' bearings they would last longer. Bear in mind they think a ball bearing is a vast improvement over sleeve bearings(far more common).

Assuming the tighter clearance did NOT cause heat problems from 'running' I would think a C1 would be a better choice if available. However there IS a $$$$ tradeoff here. IMHO Only the single bearing quill bearing justifies the added expense/availability effort.

Bill I would like to hear your reaction to all I have said in this post. TIA

[bucksaw]

Let's be very explicit here:

The drive shaft bearings are ???? ?? ?? ????
The single quill bearing is ???? ?? ?? ????
The control/idler shaft bearing is ???? ?? ?? ????
The Motor bearings are ???? ?? ?? ????

We have been throwing part numbers around and I for one am NOT at this point sure which is which.

Industry standard numbers (NTN uses these I believe)

• All bearings radial clearance should be standard (C2-C3) with exception of the single bearing quill where a C1 bearing is desirable if available.
• The drive shaft bearings are 6205 ZZ
• The quill bearing is 6202 ZZ 5/8" (C1 if available for a single quill)
• The control/idler shaft bearing is >>>> Water pump shaft...shaft and bearing are one and is un-repairable by the average joe.
• The Motor bearings are:
  • AO Smith 3/4 is 6203 ZZ
  • GE 3/4 is 6203 ZZ

Fafnir Numbers:

• The drive shaft bearings are 205KDD
• The single quill bearing is 202KDD5
• The control/idler shaft bearing is >>>> Water pump shaft...shaft and bearing are one and is un-repairable by the average joe.
• The Motor bearings are:
  • AO Smith 3/4 is 203KDD
  • GE 3/4 is 203KDD

Any corrections here.

[JPG]

Double check fafnir drive bearing???

P.S. Dave corrected fafnir drive shaft bearing to 205KDD on the other post which was a copy of this post.

[tdubnik]

Industry standard numbers (NTN uses these I believe)

• The drive shaft bearings are 6205 ZZ
• The single quill bearing is 6202 ZZ 5/8"
• The control/idler shaft bearing is >>>> Water pump shaft...shaft and bearing are one and is un-repairable by the average joe.
• The Motor bearings are:
  • AO Smith 3/4 is 6203 ZZ
  • GE 3/4 is 6203 ZZ

Fafnir Numbers:

• The drive shaft bearings are 202KDD
• The single quill bearing is 202KDD5
• The control/idler shaft bearing is >>>> Water pump shaft...shaft and bearing are one and is un-repairable by the average joe.
• The Motor bearings are:
  • AO Smith 3/4 is 203KDD
  • GE 3/4 is 203KDD

Any corrections here.

The SKF Part numbers would be:
Drive Shaft: 6205 2Z
Single Quill: 6202 2Z ??? (SKF uses special feature numbers to designate non-standard shaft size and I don't remember what it is)
AO Smith 3/4: 6203 2Z
GE 3/4 : 6203 2Z

[edward]

Bill's point, as I understand it, is that a C1 bearing compensates for a problem with the single-bearing quills. You can buy a double-bearing quill with C3 bearings and it'll work famously. But single-bearing quills have a drift (right word?) that makes them less precise, which the C1 corrects because it is beyond the standard.

For me it boils down to $$ (I bought an old SS and fixed her up because I can't afford anythign else) and time (I'm sick of waiting to use this thing). Maybe I'll get the $10 bearing, and if I become dissatisfied, give Bill a call.

Sorry I'm thinking out loud here. After almost 200 posts, I've grown oddly familiar with this thread.