Shopsmith Forums

I haven't seen this topic addressed in awhile so I'm bringing it up.

A couple years ago I rebuilt a speed changer of a 10 ER. The owner contacted me and asked me to rebuild it again. When I got it the bearings were shot. Turns out the the owner didn't lubricate it correctly.

He lubed the oilite bearings with red axle grease. Once in awhile he would blow the bearings out, wash them with brake cleaner, wipe grease on the shaft and reassemble it. There wasn't much brass left.

I advise to blow the bearings out frequently and lube with a couple drops of 30W Non Detergent oil. Never wash them with any type of solvent. Never lube with a heavy grease.

I've been told the grease holds the wood dust. The dust pulls out the lubrication and causes the speed changer to run hot. Thus, ruining the bearings.

What are your thoughts on this? Agree? Disagree? How do you lube yours?

Tom

I have a 10er,but it does not have a speed changer.

I work on John Deere 200 series garden tractors that has what Deere calls a variator speed changer. What it does it changes the speed of the garden tractor.
I has a center sleave like SS speed changer has.

To lub the center sleave I use powered graphite.
I remove both belts from the speed changer, then what I do to cleans the center sleave so that it can slide back and forth I use brake cleaner. After the brake cleaner is gone, spray just a little brake cleaner on.
Then apply the powered graphic on, the brake cleaner to help work the powered graphite in.

the powered graphite should not attract any thing to cause damage to the speed changer
I hope this helps

The bearings are sintered bronze(oilite). Only oil should be used and not excessively so(crud attractor).

Same oil as for the Mark 5/V sheaves(#10 machine oil).

Oil often, but not excessively so.!

I agree with JPG. The manual calls for cup grease which is an oil based grease with a thickener. However sintered bronze bushings work just fine with light oil. I would never "clean" them since they soak up and retain the oil.

lyall suggested powdered graphite but that is not the correct lube for sintered bronze bushings.

I use turbine oil with a zoom spout. It is a light weight oil and the zoom spout works great for lubricating the MK 5/V sheaves. It is available at the big box stores.

I would go with oil also. Those bearings have a matrix structure that holds oil and you can actually soak them in a hot oil bath then cool before installing to take care of any storage oil loss.

Ed

I agree with the oil lube recommendations, based on the operating speed.

I once designed a CNC retrofit system for a machine tool, where a high-speed servomotor was spinning a existing shaft that ran in bronze sleeve bearings. The machine had an automatic oiler system that added a few drops of oil to each bearing every few minutes. Even so, we had to limit the servomotor to about half of its full speed capability, to avoid cavitating the oil in the bearing.

In operation, the lube oil is supposed to form a “hydrodynamic film” between the shaft and the sleeve bearing. Under the proper conditions of surface speed, oil viscosity, and bearing load, this oil film will support the shaft such that it never even touches the bearing. But if the oil cavitates due to excessive surface speed, the film breaks down and allows metal-to-metal contact.

Our mechanical engineer ran all those numbers, and I’m certainly no expert on it. But I did find a couple of articles online suggesting that grease shouldn’t be used at surface speeds above 200 FPM (feet per minute). Using rough dimensions and RPM’s, I calculate that the surface speed of the speed-changer bearing can easily exceed 500 FPM.

Oilite bearings for this speed range are generally lubricated with a turbine oil and impregnated with oil by vacuum. They are self lubricating and wick oil to the heat area caused by friction.

Shopsmith to my knowledge never provided any felt washers to allow them to both seal out contaminants and wick replacement oils applied to the felt washers to allow wicking in of replenishment oils.

Some printing equipment I used to service had a felt washer, a fender washer and an E-Clip to hold it against the body of the oilite bearing, allowing it to draw in lubricant as needed.

I have attached a PDF that discusses Oilite bearings, types and applications that goes into detail on the subject. Good info in general for anyone who has oilite components.

Everett

oops, I didn't read this thread until after reading the "instructions for installation and operation - VARIABLE SPEED CHANGER" and then lubing the bearing with grease.

What should I do now?
- run it with grease and use oil next time
- clean out the grease and replace with oil now
- or...

I'm still cleaning and reassembling; this hasn't been my first setback and I doubt it will be the worst...

Thanks

curmudgeon wrote:oops, I didn't read this thread until after reading the "instructions for installation and operation - VARIABLE SPEED CHANGER" and then lubing the bearing with grease.

What should I do now?
- run it with grease and use oil next time
- clean out the grease and replace with oil now
- or...

I'm still cleaning and reassembling; this hasn't been my first setback and I doubt it will be the worst...

Thanks

I would just wipe off all the grease you can and apply a few drops of turbine oil. After a short time of running wipe it off again and add a bit more oil. Just don't over oil it. The grease won't really hurt it.

jsburger wrote:

curmudgeon wrote: What should I do now?
- run it with grease and use oil next time
- clean out the grease and replace with oil now
- or...

I would just wipe off all the grease you can and apply a few drops of turbine oil. After a short time of running wipe it off again and add a bit more oil. Just don't over oil it. The grease won't really hurt it.

Thanks for the advice John. I'll replace the grease with turbine oil before reassembling. Is AeroShell 500 suitable?

-Steve