Burning old grease out of bearings, "How To" or "Don't Do?"

[Ratfink1962]

Seriously, go read this article, it could save your life.
http://www.brewracingframes.com/id75.htm

I read that article years ago and I warn anyone I know that welds, but the issue there is not burning the brake cleaner, it was the MIG and the brake cleaner together, still though, after that article I only use the stuff to blast stuff off, never before welding. When I need to clean a part of grease or whatever before welding, I use the torch.

I agree, it was because of the brake cleaner and argon gas combined while welding.... but if it were me, I dont think I would want to chance it by applying any form of heat.

With all that being said, I believe heating up the part to soften caked on grease is a great idea, just dont overdo it, and everything will be okay.

 

[petesponies]

If you just use a propane torch and get the grease hot, no damage will happen. Now if you use acetylene and heat it red . . different story

 

[Voyager Al]

I would think that a safer way would be to use a heat gun. It will never get red-hot, and yet get hot enuf to soften the grease. I may try this, as I have a few heatguns around from my window tinting business.

 

[tanksalot]

Tide & water 50 % of each let them sit & wash = good as new ..

 

[Voyager Al]

Your old grease gotta be alot softer than the grease I have run into. Im talking a compound thats as hard as shellac. Water and ol intensified tide aint gonna get it. Nope...

 

[mikeeebikey]

Exactly what I was going to post! Thanks. Some steels are quickly effected by heat, especially stainless steels and moly steels. Stainless gets hard, moly gets softer, usually.
I like carb cleaner, lett the bearings soak in it overnite and they'll be clean. If you know someone in the drycleaning buisiness get some perchlor/trichlor-ethane(do not inhale, ingest, envelope flesh or dump down a drain, ever) and clean anything dirty, I don't care how dirty!
9 times out of 10 bearings that're grease dried are going to be bad, just replace them if possible.

You might well get away with it, but if your heat input and dissipation rates are not equal, you can effect the "temper" as well as any type special surface treatment with as little as 200 Fahrenheit, though not always, and probably not much. If you hit 400, you've changed it. The center cone hot-spot of a Harry Homeowner propane can be a couple thousand degrees, That's blacksmith hot. :|

 

[yoothgeye]

I would think that a safer way would be to use a heat gun. It will never get red-hot, and yet get hot enuf to soften the grease. I may try this, as I have a few heatguns around from my window tinting business.

Heat gun won't do what I do with a torch, haha.

I'll let everyone know when I have a bearing failure from a set that I burned the grease out of.

It has been an interesting conversation with LOTS of good information, technical and personal.

I just wanted to bring it up and see where it went, most people will never do this and even more would never think about doing this, but I will keep doing it.

I don't really care that much about changing the temper of the ball bearings or cages, these are for kids bikes and junk bikes and things, nothing "high performance."

I need to make a video of how I do it just to clear up my process... it's violent! :shock: I actually boil the old hard grease out of the bearings, I never have to use another method to get the grease out, it comes out all by itself, so there is a lot of heat involved. :lol:

 

[petesponies]

You do need to care about changing the temper, regardless. But, like I said, a simple propane used to soften the grease is not going to do that.

 

[deorman]

One way you can tell is just before it glows, oxidation may become visible. "Reading" the color of the metal showing through the oxides is how temperature is judged for hand-tempering steel, if it's red hot the oxides are no longer visible and you are at annealing temperature, and the metal will probably be softer afterwords. Quenching may harden it somewhat, surface or whole, maybe too much. In any case, I'm guessing the grease is probably long gone before it gets that hot.

 

[The Renaissance Man]

LET ME TELL YOU SOMETHING! This seems like a potential hazard.

 

[petesponies]

I'm guessing the grease is probably long gone before it gets that hot.

That is the entire point :lol:

 

[yoothgeye]

I'm guessing the grease is probably long gone before it gets that hot.

Bingo! And I've got some clean bearings fast.