Loose bearing cup in wheel hub

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has anyone else ever had a Loose bearing cup in a wheel hub- i had not
and it was making a heck-uva racket, an I could not get the bearings adjusted to save my life

The cup was spinning freely in the hub, so i took it out, and first tried grinding divots around (the surprisingly hard) cup exterior, to raise a burr, but no luck

so i used my 110 fcaw welder, clamped the cup in the ground, pressed the trigger and let go, then touched the wire to the cup exterior.
a tiny spark and a tiny bump. time like 25 all around the out side, then a quick file, then it fit(forgot to take pictures of these "cold welds"
but it worked, no more slippage
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Locktite makes a few different bearing retainer compounds for different gaps and applications. I've had a high degree of success with them on damaged truck axles and spindles. Another trick is to center punch around the perimeter of the softer surface which leaves a raised edge to grip the bearing. There were a few times I used both methods to make repairs when the damage was severe.
 
I can totally see the cup in/on your example
Flare out the the fins on this, then just fit it in, then bang 'er out
the flip side is easier, the tool fits better...
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I don't know how he does it dude. Now I am going to have to ask him. This doesn't look very serviceable
View attachment 137723
Heat it in an oven 400f +, the hub should expand slightly more than the bearing. Then use an old screwdriver with a custom bent tip or a mini pri-bar to tap under the bearing and lift it. Work fast and wear heavy gloves.
 
Locktite makes a few different bearing retainer compounds for different gaps and applications. I've had a high degree of success with them on damaged truck axles and spindles. Another trick is to center punch around the perimeter of the softer surface which leaves a raised edge to grip the bearing. There were a few times I used both methods to make repairs when the damage was severe.
my center punch barely left a mark - ha! But yep this was my basic plan
good to know there is a product for this.

If you look closely at the pic of the hub you can see some bearings inside the hub!
 
Yeah. I see the race/cup, but I have no idea how that is held in there, but I can definitely see the seam
Sheldon brown?
 
The op's hub is the cheapest chinese junk made. Stamped sheet medal cups, loosely pressed in to tube made of rolled over sheet metal. I have a bunch of these for teaching. To show how bad hubs are designed and manufactured. There is no back support for the cups. Many box mart bikes aren't assembled well so the cones can loosen up on the axles and turn inward as the bike rolls. They will crush the cups and keep going. The cups and cones are painted at the factory. A poor substitute for precision grinding. These are the hubs found on most boxmart bikes that sell for under $150. The cost of manufacture of these hubs is probably under $0.10 usd each. They are just pressed together and painted. Most need to be cleaned (to get the ground up paint out) and regreased and properly adjusted after 20 miles from the factory. Even then they won't last 1000 miles due to using mild steel for bearing cups instead of hardened steel.



Here is another that was pressed together but fell apart. In this case the cup & flange is a single forged part. The cups' bearing surfaces are somewhat smooth. A 1980s era hub. We thought these were cheap hubs at the time but the latest (above) are much worse. you might think the spoke tension would hold them together but that's not always the case.




A better hub has an aluminum body with a pressed in steel cup. The aluminum supports the cup far better. A machined aluminum body can be square, centered and plumb so the cups are in parallel planes. In this photo we see a too-soft steel used for the cup. A previous home mechanic put in 1 too many bearings and the bearings did not turn in the cup. the result was indentations in the soft steel cup and the cones and bearings destroyed. This was a Japan made hub from the 1970s.




This is Sovos brand free hub used on many mid range bikes. This one was from a Cannondale bike. The bearings were too tight and crushed the thin cup which is typical on most free hubs.
 

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