Cleaning caged bearings

[Airbear]

I'm surprised that you don't understand how it can be bad for an un-lubricated bearing to be damaged by spinning it way faster than it was designed to spin. In fact, I'm dumbfounded.

Dear Dumbfounded: I think it's the "... killing you from the flying shrapnel" bit along with the "This has actually happened many times believe it or not." bit that might be in question.

[richard t]

I'm surprised that you don't understand how it can be bad for an un-lubricated bearing to be damaged by spinning it way faster than it was designed to spin. In fact, I'm dumbfounded.

Dear Dumbfounded: I think it's the "... killing you from the flying shrapnel" bit along with the "This has actually happened many times believe it or not." bit that might be in question.

spinning any kind of machine with dry bearings is bad, I've seen a lot of bearings fail in my work over the last 45 yrs, but I've never seen one throw pieces very far. If somebody can spin a bearing by hand fast enough to make it fly apart, I'd like to sit with AirBear and watch them, from a safe distance of course.

[DanielMc]

If somebody can spin a bearing by hand fast enough to make it fly apart, I'd like to sit with AirBear and watch them, from a safe distance of course.

Always strikes me that people would pay good money to watch machinery self-destruct in a spectacular fashion. A bit like running old motorcycles, but cheaper and with less audience participation.

[Deleted User 287]

If somebody can spin a bearing by hand fast enough to make it fly apart, I'd like to sit with AirBear and watch them

I don't think spinning a bearing by hand is the same as spinning it with compressed air.

I have to side with ZM on this one. I wouldn't do it with any bearing that I was planning on reinstalling in the bike.

[melville]

Sounds like a job for Mythbusters.

The operative word is job.

I'm with Charlie on this one. I can't even see the point of it being (very) bad for the bearing as there is no load on it and it's just spinning happily.

Chuey

Didja ever work with the guy who soaked freewheels in the parts washer and dried them with the air gun? I worked with that guy. We had to give him an extension hose to take that out into the alley. When we weren't pissed off at being bombarded with flung solvent, we were entertained by his musical noodlings.

Anyway, he'd get freewheels spinning to probably several thousand rpm, and the normal operating environment for them is less than 500 rpm. Never had one come apart.

[bbelk]

I saw a picture of a guy who had been lobotomized by a grindstone coming apart. I still think about that when I use mine. On a thread a long time ago we talked about how long an Airhead would run without moving. someone suggested that we test that on a parts machine and take bets on it. Where would be the safe place to stand for that test. Locked throtle at 5000 RPM on the centerstand.

[dougie]

I saw a picture of a guy who had been lobotomized by a grindstone coming apart. I still think about that when I use mine. On a thread a long time ago we talked about how long an Airhead would run without moving. someone suggested that we test that on a parts machine and take bets on it. Where would be the safe place to stand for that test. Locked throtle at 5000 RPM on the centerstand.

Rumour has it that dynamite makes a squeal just before it blows up, but they can't find anyone to do thee research

[Chuey]

Dear Dumbfounded: I think it's the "... killing you from the flying shrapnel" bit along with the "This has actually happened many times believe it or not." bit that might be in question.

Charlie, in ZM's defense, or in the interest of clarity, yes, I did agree with you that the flying shrapnel bit sounds far fetched to me. But he is right. I did say that I doubt harm is done to bearings that are spun by air when unlubricated. The bearings I'm thinking of are precision made and hardened. I just don't see how it could be an issue.

I'm not saying you should do it, but nobody has said what they think happens if you do that. Someone said something about spinning them so much faster than they are intended to spin. How fast does a steering bearing spin? Spinning it at all is faster than it spins in that use. Of course, that has nothing to do with the issue being discussed, but it is a fun little exercise in how we say things.

I would like someone to say what they think happens to an unloaded dry bearing if it is spun fast. That is, other than killing people.

Chuey

[Chuey]

Didja ever work with the guy who soaked freewheels in the parts washer and dried them with the air gun? I worked with that guy. We had to give him an extension hose to take that out into the alley. When we weren't pissed off at being bombarded with flung solvent, we were entertained by his musical noodlings.

Anyway, he'd get freewheels spinning to probably several thousand rpm, and the normal operating environment for them is less than 500 rpm. Never had one come apart.

Melville, you know how sometimes you just do something because that's how it's done? Then later you think about it and a question mark appears above your head? That's what happened to me with regard to solvent tanks in my shop. After having one for probably four years, I walked into the shop one day and was disgusted by the smell of it. It left almost a "mist" in the air. I thought about how my co-workers and I were breathing in that fog constantly every day. I called Safety-Kleen and had them pick up the tank. I'll admit they are handy but I started thinking of it in the "quality of life" sense. And it didn't make sense. Besides, cleaning chains in solvent tanks always made them run noisier and people replaced them faster than if they were just wiped down and lubed.

And yes, we have spun some stuff up really fast. Not only freewheels but my favorite is jockey wheels. If you think about it, if it was going to do damage, a simple bushing like most jockey wheels have would be the most likely to be damaged. Dude! They love it? They go wheeeee! Then, you can turn them around and spin them the other way. Never seen a problem from it.

Chuey

[Deleted User 287]

Dude! They love it? They go wheeeee!

"Cheap thrills, in the back of my car
Cheap thrills, how fine they are
Cheap thrills up and down my spine
I need it, I need it, 'cause it feels so fine now..."