# Cleaning sealed ball bearings, questions about stuff.



## Ttrees (15 Feb 2022)

Hello folks
Been looking at some videos online about cleaning and maintenance of ball bearings 
but haven't come across a good video on the subject.
Mainly the comments is where anything is to be gained from.

(I have some questions after my rambling paragraph.)

I am pondering/toying with the idea whether to replace the newish SKF explorer bearings I have, 
in favour of trying out the old Koyo bearings which were in the machine previously.

Why?, well seems that those SKF bearings have more of a chamfer on the outer race compared,
and the application is for bandsaw wheels with a non shouldered bore.
As you can see the SKF on the right and Koyo's on the left.

These bearings were in a bucket at the folks place for years, and I'm guessing have plenty of grit embedded.
Cleaned up two of the three (one got mangled somehow)
with the possible intention to install them sometime.

The pair which I cleaned from the outside with a thin ruler, are not scratchy or anything, 
but I dare not use them yet, just seeing if it may be worth trying.
I've got a new tooth brush and a new can of thinners if that's any good for the job?

Would make a seal removal tool if one exists, most seem to either suggest a pick or a Stanley blade,
some remarking on youtube comments that one should remove them by prying on the inner race
side of the seal, as damage would not migrate out of a damaged seal due to the centrifugal force.
Is it more difficult to remove I wonder?

I have at least one seal which I think has been damaged so can do some tests with.
Not yet looked at as closely at them, as I likely need to.

Not sure what grease I need, seen folks mention not to mix as one type incompatible with the rest.
One of these bearings has black grease migrating, don't know if that means it's toast?

Me auld fella has got some, likely the cheapest stuff one can buy for farm jobs.
I don't really want a big tube of messy grease in the workshop forever, so might just use some of that if suitable, have to look up whatever is on the label yet though.

I've read NOT to go for the ever migrating silicone, which is the pinnacle of my knowledge as it stands.



Best removal tool for rubber seals, do you poke the other one out from the inside?

Are paint thinners and toothbrush suitable for removing old grease, to inspect the races?

Best/worst NON silicone grease for for the job for the bandsaw, does black grease migrating mean those races are scored?

Is there anything else I'm omitting?

Thanks folks

Tom


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## wallace (16 Feb 2022)

Sometimes a bearing can seem perfectly fine in the hand when rotating, its not until the intended load is applied does the worn bearing appear. 
You could just remove one seal or even both and run them as open bearings.


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## Ttrees (16 Feb 2022)

Thanks Wallace 
I'll be making a nice wee tool for the job of taking off those seals.
Not seen one, but seems a flathead screwdriver like say a phase tester is used sometimes on biggins, which is a bit more encouraging to see, compared to some using fish hooks and picks.
Seems one could make some kind of leaf like tool with no corners to get them out easily.

Must be the algorithm as I can only find kids repairing skateboard bearings, and no engineering channels have info on the subject.
Still haven't found one, and been looking.


Only put the old bearing in, as I needed to insert and remove it a few times to get the right fit of the spacer, and not gonna run the machine yet for fear that it would seize and enlarge the inside of the hub.

These were good (I think) before I removed them, as the issue was with the spacer all along, plus other stuff.
Doubtful they still are after being sat in a pot in a gritty environment, so being cautious.

Will likely be attempting to clean the worst first, just for fun.
Might learn something, or more importantly what not to do.

Love to read a link should anyone have one.
Not had any luck myself.

Thanks
Tom


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## Jacob (16 Feb 2022)

Why bother I'd just leave them alone until they start squeaking. They'll still have plenty of mileage in them while you wait for replacements and won't cost a bomb.
Write down the part numbers before you put them back.


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## Spectric (16 Feb 2022)

For the price of new ones just replace them as it gives you a known starting point and removes a source of future issues. One thing to bear in mind is not to overpack a bearing with grease, they don't need craming.


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## Ttrees (16 Feb 2022)

Which ones are you talking about Jacob?
The unsuitable new "premium" ones which have rounded shoulders,
or the old ones which were likely original.

The whole get her done approach won't help matters for large cast iron bandwheels, which likely have a bit of wear already with the shenanigans of previous folks efforts, and my neglectful use of it after,
and I want this machine to last.

Can't afford new ones, and can't be sure I'd be able to source the right ones either.
That extra surface area on both inside and outside is more insurance IMO.

Take a look at the other S45 on "the other place2" and have a guess why that happened.
Could be a mix of Friday evening special casting error,
inadequate setup, neglect, and possibly those kinda bearings could have helped matters, I don't know, but I can't afford to take any chances.

That extra wee bit of area could make the difference here, as my machine has been through the thick of it, so much so that one would have expected much the same kinda thing.

Cheers though all the same.

Tom


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## Jacob (16 Feb 2022)

Ttrees said:


> Which ones are you talking about Jacob?
> The unsuitable new "premium" ones which have rounded shoulders,
> or the old ones which were likely original.
> 
> ...


Shouldn't be difficult to replace if you get the right part number - they are a standard items off the shelf from lots of places, unless very unusual. They are consumables for replacement, not maintenance, as per motor wheel bearings.
Other than that I haven't much idea!
PS compared to motor wheels they'll get a very tiny battering in use and as long as they fit, other details may not matter





Simply Bearings Ltd - Ball Bearings, Oil Seals, O-rings, V-Belts, SKF







simplybearings.co.uk


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## Ttrees (16 Feb 2022)

That would be appreciated to know if it were easy to source, or if most of the rubber sealed bearings have more chamfer than others.
I guess it's hard to tell from most searches, haven't checked though.

I can get shielded FAG bearings local, bought ones not too long ago,
and it appeared the edges are nice and crisp compared, not that I was concerned
about that for the motor,
And no clue whether all of the bearings from them (FAG) are like that.

Seems there could be nothing wrong with the older ones,
and find it hard to fathom why bearings aren't reconditioned a bit more often.

Strictly a hobby use this machine will have, as in I would halt everything straight away should things not be running as it should,
so I don't think I'm being unreasonable with my proposition,
and I guess I would be able to spot some wear once the grease is cleaned off.

Thanks

Tom


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## Jacob (16 Feb 2022)

Ttrees said:


> .....
> 
> Seems there could be nothing wrong with the older ones,
> and find it hard to fathom why bearings aren't reconditioned a bit more often.
> ......


Because sealed bearings are no more expensive to make and very easy to replace. They are intended as throwaway. The days when you would replace ball bearings are long gone!


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## Ttrees (16 Feb 2022)

I suspect with this fast paced world that be the case, 
but being a scrimp I might as well try.


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## Jacob (16 Feb 2022)

Ttrees said:


> I suspect with this fast paced world that be the case,
> but being a scrimp I might as well try.


Even push bikes are mostly disposable sealed bearings nowadays.


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## Ttrees (16 Feb 2022)

Aye, but there's probably not 9 million bandsaws in Beijing


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## Ttrees (17 Feb 2022)

Seems from some googling, like white spirit would be better for the job 
as some thinners and the likes of acetone, are more likely to leave a residue?

Might have a go this evening or tomorrow at attempting a bathing the old ones.

Tom


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## Jameshow (17 Feb 2022)

How about taking a hypodermic needle and injecting grease through the shield and into he bearings? 
Not done it myself but worth a try?


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## Ttrees (17 Feb 2022)

I have read that, some do that to shielded bearings, but I should be able to take off the rubber seals easily with a wee tool, likely something like some tough steel bit of grinding and some needle filing.

Need to inspect these bearings to be sure they won't stand the chance of sizing in the wheel, which would score the inside of it.
(See other forum to get an idea of what that sort of damage can look like.)

Will hopefully be attempting to give them a soak in white spirit for a day or so, 
and see if that works.

Cheers
Tom


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## deema (17 Feb 2022)

IMO if they are standard deep groove bearings, it’s a false economy to reuse bearings / use bearings where the grease has turned gummy. Your more likely to end up with the bearing seizing and damaging the journals which is a more expensive and bigger job to rectify. I never reuse bearings, or old sealed for life stock on active shafts. Old stock open bearings designed for the user to grease up, yes.
For a dusty bandsaw, removing the seals is only going to allow the dust in and they will fail quickly, you won’t be able to clean them fully unless you remove both seals.


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## Fergie 307 (17 Feb 2022)

Very much doubt you will be able to get the seals off without damaging them, and doubt you can get replacements. The bearings are designed to be thrown away when worn. Take the old ones to any bearing supplier and I am sure they will be able to match them. Really not worth messing about with for what they cost.


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## Sandyn (17 Feb 2022)

I would just replace the bearings, but you want to have a try to refurbish, so why not. I would use petrol, paraffin, penetrating fluid or white spirit, whatever is handy. you might be able to remove the seal with a sharp point. Submerge the bearings in the fluid and keep revolving to get all the old junk out. Blast with high pressure air. I wear a mask when doing it, there will be a cloud of muck come out of the bearings. Repeat several times as necessary. I would finally wash the bearings with really hot soapy water to get the last of the muck/residue out and dry with high pressure air. I have never actually done this, but if I did, that's what I would try. Also inspect the ball bearings for wear. They start to look like a well sucked gobstopper. Good luck


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## Inspector (17 Feb 2022)

I've done it before with small bearings out of the controls in old aircraft. They were the kinds with a circlip retaining the seals. I would take the seals off both sides and then soak the bearings in Varsol, Shellsol, Stodard Solvent and work the hard grease out with acid brushes as it softened. When done the bearings, not the seals, got a soak in MEK or Acetone. If blowing with air make sure you don't spin them or you risk damaging the balls and races or worse they fly apart. Once clean and inspected for damage and corrosion I would repack them to no more than 3/4 full. It was a long process and after doing it a few times the powers to be clued in the it cost more in time than to replace them with new and they lasted much longer to boot. If I had no other choice I would clean and repack otherwise new it is. The kind of seals in your bearings don't take well to being removed and replaced as they are too easy to damage. Your time so have fun. It's not to late to save your sanity and buy some new ones.  

Pete


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## TFrench (17 Feb 2022)

The surface area difference from having the chamfer is minimal, especially given the application. There's a reason there's no videos out there on doing it - might as well wash out and iron your bin bags as well...


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## Ttrees (18 Feb 2022)

Thanks for your thoughts folks

Not being at all knowledgeable about this sorta stuff, so it's very nice to read that there's various ways of cleaning them out.

It would seem to me like white spirit will be best, as I don't have any solvents to get rid of any residue, should I use paint thinners for the job.
No compressed air, but think I might manage with patience and toothbrush instead.
Hot water just feels wrong to me, but will if nessecairy should I not get things shiny and not tacky.

Bought some lithium grease for 3 euros
Lithium EP2 multi purpose -20c to +140c in a brownish tube.
Guessing this is the stuff, but seen some red stuff which I was considering either.
Not to worry, I will see how things go.

Haven't made a wee tool for the job of seal removal yet, good to hear some warning
as those utubers seem a bit confident with a pick or blade.

Eager to see how good they turn out, and should they be pants, then nothing lost but a hour or two and a 3 quid tube.
Have some other bearings which I could also do if it goes well, so hopefully the grease tube can earn it's keep in the press.

Thanks for your comments folks
I'll make an update when I get back to this.

Tom


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## Inspector (18 Feb 2022)

Note that paint thinner and mineral spirits are similar to the solvents I mentioned so disposal is still the same. You take the oily film (minimal) off with Acetone type solvent but why? You’re going to put grease on them anyway. If you’re going to Loctite them in then you would degrease the outside.
Pete


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## OCtoolguy (18 Feb 2022)

Many years ago, I was enrolled in classes at General Motors Institute and the instructor told us to NEVER wash out a bearing with any type of solvent as once dried, grease will not adhere to the bearing balls or rollers. I did in fact have to try that just to satisfy my own curiosity and it is true. I washed a ball bearing, wiped it dry with a lintless cloth and then blew it out with compressed air. I then tried to apply a good coating of wheel bearing grease and it would not stick. I forget now, it's been 60 years, what I finally had to do to get the grease to stick. Another type of cleaning, possibly hot soap and water. The solvent leaves something behind that will not allow the grease to adhere.


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## Phil Pascoe (18 Feb 2022)

Sandyn said:


> They start to look like a well sucked gobstopper. Good luck



I replaced bearings on my lathe that were shot with used bearings off an identical shaft - they looked absolutely perfect and rumbled to the point the lathe was unuseable. I can understand someone taking time and trouble to reuse old unobtainable or ridiculously expensive bearing, but for ffs for the work involved just replace them. Every time.


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## Phil Pascoe (18 Feb 2022)

OCtoolguy said:


> Many years ago, I was enrolled in classes at General Motors Institute and the instructor told us to NEVER wash out a bearing with any type of solvent as once dried, grease will not adhere to the bearing balls or rollers. I did in fact have to try that just to satisfy my own curiosity and it is true. I washed a ball bearing, wiped it dry with a lintless cloth and then blew it out with compressed air. I then tried to apply a good coating of wheel bearing grease and it would not stick. I forget now, it's been 60 years, what I finally had to do to get the grease to stick. Another type of cleaning, possibly hot soap and water. The solvent leaves something behind that will not allow the grease to adhere.


I wonder what the bearings were cleaned with before lubrication when assembed?


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## TheTiddles (18 Feb 2022)

I must be tired, almost sounds like you want to replace some premium bearings with old dirty ones after you’ve fudged around with them?

Sounds about as good an idea as reusing a stretched bolt or a cracked o-ring.


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## Sandyn (18 Feb 2022)

Sometimes it's good to try to do this, just for the fun of it and to see if you can. It might work, it might not, but it's how you learn. Go for it!!!


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## Ttrees (18 Feb 2022)

OCtoolguy, kudos for mentioning this, I will be doing a wee spot test first,
to be sure now thanks a million.
Just for clarification there was no reason to have swapped these bearings in the first place, and I was thinking it was them which was to blame rather than all the other things
which was the reasons.

Thanks for mentioning all these solvents Pete, although familiar concoctions I've read of before, I had to google to make sure which each was.

Not sure if I mentioned that I planned to keep a very close eye on these bearings with the intention of getting new ones after a bit of testing and light use, say not challenging the machine and only running for say 30mins a week max kinda thing.

I will be taking the bearings out anyway, only installed the old one just to make sure I didn't damage the SKF newer one, whilst I was getting the fit right making a new spacer for the wheel.
Now I have the fit right, I am going to make two more,
the part made below could be more accurate,
(plastic got squished a bit in the vice whilst drilling, so the hole is a bit shoddy)






I think there's more chance of getting everything a bit more solid with the original bearings.
Guessing there inst much mileage on this machine to begin with, as it was a Friday lemon, possibly only getting as much run time as I've put on the newer bearings.

Even though I've got the fit right for the top wheel, I might well end up faffing about with the bottom wheel, or possibly not going near it either.
Gotta do some alignment checks as the wheel will sit further out of the shaft with the new part,(I have another thread about those spacers), 
and the pulley is sitting as far out on the motor shaft as I dare to use.
Quite a distance, one could possibly take a little of the face of the back of the shaft to sit the wheel in further, and get that pulley more on the shaft.
Have the original measurements written down for it, something like below as is now.
Probably not good.




Gotta figure out those wee things, along with the play about with wheel protrusion on the top wheel and other tests, etc
so that might explain why I wish to use old bearings for a while...
plus I'm skint at the moment.

Thanks
Tom


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## Sandyn (23 Feb 2022)

Today, I had to do a repair on my bike and happened to notice some rust muck coming from my bottom bracket which has a BB30 bearings (42mm Outside and 30mm inside Dia.) When I took the pedals off, and rotated the bearings, they were full of crud. I picked out the bearing seal, very very easy, without damage. I cleaned the bearings using anything I could spray inside, then high pressure air to get the grime out. The bearings are knackered, but it will keep me going for a while yet until I can get replacements and make a custom tool for removing the circlips and a make a bearing press on the lathe, or I might try printing a 3D tool.


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## Sandyn (23 Feb 2022)

OCtoolguy said:


> Another type of cleaning, possibly hot soap and water. The solvent leaves something behind that will not allow the grease to adhere.


Really interesting to know.


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## Ttrees (23 Feb 2022)

Hi again, sorry been a bit late to reply back.
Have some photos of a bearing puller tool which I made from the end of a masonry nail,
and had a test of the tool.
There was a lot of crud, and possibly fatigue of the edge of the rubber, and possibly damage from me pulling them off too, didn't try cleaning them to inspect properly, 
and put them away as had some dusty work to do.

At the same time as doing some turning my lathe bearings started rumbling,
not to mention the drill is needing attention aswell. (definitely replacments needed as are bad)
Quite instant I would say, well in the case of the lathe anyway, so I must investigate that.

As you might have guessed this made me have second thoughts about using the old ones, for something quite a bit more crucial than other applications, so going to stick back in the newish one, as I've still not made the other new spacers yet.

Hopefully I'll be able to report back with some queries I've made recently on a few threads, and depending on how critical those bearings for the other machines are,
might be worth trying on, now I've got a big tube of grease.
Typical!


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## okeydokey (20 Aug 2022)

OCtoolguy said:


> Many years ago, I was enrolled in classes at General Motors Institute and the instructor told us to NEVER wash out a bearing with any type of solvent as once dried, grease will not adhere to the bearing balls or rollers. I did in fact have to try that just to satisfy my own curiosity and it is true. I washed a ball bearing, wiped it dry with a lintless cloth and then blew it out with compressed air. I then tried to apply a good coating of wheel bearing grease and it would not stick. I forget now, it's been 60 years, what I finally had to do to get the grease to stick. Another type of cleaning, possibly hot soap and water. The solvent leaves something behind that will not allow the grease to adhere.


Ive used WD40 to wash out open bearings in the past and then put grease back and that didn't stick either so must be the same solvent thing


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## Phil Pascoe (20 Aug 2022)

If WD40 (or similar) didn't leave a coating of something there's be little point in using it, I'd have thought.


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## rogxwhit (20 Aug 2022)

Phil Pascoe said:


> I replaced bearings on my lathe that were shot with used bearings off an identical shaft - they looked absolutely perfect and rumbled to the point the lathe was unuseable.


Your method of removal might've prejudiced their future. One might withdraw a bearing by pulling on its outer race, but need to install it by pressing on its inner race, for instance. But I can't think either what you you were going to tell by 'looking' ...

Since bearings of the sort we're talking about (I think) last for ages & are cheap to buy, I've always just replaced with new ...

Re-use would be 'greener', but if it doesn't work do you really want to dismantle the machine again?


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## Phil Pascoe (20 Aug 2022)

Looked was a broad term. They were perfectly clean and revolved without slightest hint of ever being used. I was scareful removing them - it wasn't difficult - and I didn't have new ones to hand at the time. The new ones were about £40 iirc.

Scareful? Careful.


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## John Hall (21 Aug 2022)

I’ve found a brake cleaner aerosol the best thing for cleaning Grease off small items….doesn’t leave any residue


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## sawtooth-9 (21 Aug 2022)

Unless you have some VERY special tapered bearings ( e.g lathe headstocks ) - just replace them.

If you can't afford the bearing, you can't afford the machine

Very special ( and expensive ) bearings may warrant " repair " , but honestly this is rare.

The basic rule is NEVER mix lithium greases ( most common ) with bentonite greases ( usually sold as High temp bearing greases )


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## Phil Pascoe (21 Aug 2022)

Do you know why? Serious question.


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## Jacob (21 Aug 2022)

Cleaning sealed ball bearings is pointless by definition - if they need cleaning they have failed. 
Though you might get a bit of extra mileage from them if you are lucky


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## Homeless Squirrel (27 Sep 2022)

Jacob said:


> Cleaning sealed ball bearings is pointless by definition - if they need cleaning they have failed.
> Though you might get a bit of extra mileage from them if you are lucky


All my fishing reels have sealed bearings and clean out in lighter petrol then re oil with 2 drops of very fine oil for the spool bearings which get a hard kicking when casting but few drops more and performance drops off but makes them last over if left as was from new plus performance isn't so good from new.
but one way with bigger bearings is to douse in likes of comma hyper clean which apart from leaving anything clean it has an anti rust element in it then drop into a pot of heated grease so gets into bearing then once cooled bearing packed again.


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