Bicycle Mechanics - exploding nipples

usually when i work on old wheels the nipples sort of shatter when I attempt to turn them. The edges dont round, the whole part where my spoke wrench is sort of crumbles.

This happens to me a lot and its very annoying... because after this happens to a few spokes i basically have to rebuild the wheel. I use penetrating oil as a note.

and in case you were expecting something else you can watch this: look out they swear (http://www.youtube.com/watch?v=mflMPssRsl0)

Sounds like corrosion won. Why are they in such poor shape? Why do you work on so many old poor condition wheels is what I'm wondering...

Why do you work on so many old poor condition wheels is what I'm wondering...
I work at a bike co-op

The city I live in (hamilton) diverts many of the bikes headed for the dump to our co-op.. which is sweet, but everything is super old.

must be made from poorer quality metals.

Poorly maintained alloy?

Poorly maintained alloy?

rusty spoke threads?
rust has more material than the original metal form, maybe they expanded enough to cause hairline cracks in the nipples?

rusty spoke threads?
rust has more material than the original metal form, maybe they expanded enough to cause hairline cracks in the nipples?

My only experience was when I tried truing my FSA mountain bike wheels (w/alloy nipples) they sheared after only a quarter turn. Then a few more did the same thing.

but these are probably cheap wheels if they're headed for the dump.

Probably aluminum nipples. Old aluminum nipples (>1year) will typically crumble

Probably aluminum nipples. Old aluminum nipples (>1year) will typically crumble

Where did you get that idea? I haven't had one fail in at least twelve years.

but these are probably cheap wheels if they're headed for the dump.
not really usually all the parts are pretty nice... just the nipples fail.... its very frustrating

hmmm... must be the acid rain eating away at the metal in the nipple then.

you know its funny you say that because hamilton (where i live now) is a steel town and its not known for its air/rain quality...plus all of buffaloes pollution floats up here :(

That's a heck of a thread title. Imagine what it must look like to the uninitiated.

If these old wheels were ridden in wet, salty conditions and/or stored outside, you have real corrosion problems. Aluminum nipples are particularly prone to this kind of damage (and failure) but brass isn't immune either.

And, yes, your thread title did conjure up an interesting mental image. :)

you know its funny you say that because hamilton (where i live now) is a steel town and its not known for its air/rain quality...plus all of buffaloes pollution floats up here :(

The buffaloes are bad about polluting here in Oklahoma too but it doesn't float.

If it had non stainless spokes, rust may have expanded the threads not only binding them but stressing the nipple radially. Your added stress of trying to turn them finished them off. Even with stainless spokes, nipples sometimes get bound to the spoke and trying to turn them crumbles the flats.

3 suggestions which will help on borderline cases.

1- use a 3 or 4 corner spoke wrench when working on tight or old wheels. It isn't necessary with good wheels but helps with ones like what you work on.
2- add a drop of penetrating oil to each nipple where the spoke emerges, then spin the wheel to drive it in. Set the wheel aside a few hours for it to work it's magic.
3- cut down an old broom handle, or broken hockey stick if you're Canadian, to about 18" or half a meter. Wedge it between the rim and hub, so that you can use it to push the rim across a bit and take some tension off the spoke you're turning. Don't overdo it, just lighten the load a bit. This will greatly reduce the torque needed to turn the nipples.

3- cut down an old broom handle, or broken hockey stick if you're Canadian, to about 18" or half a meter. Wedge it between the rim and hub, so that you can use it to push the rim across a bit and take some tension off the spoke you're turning. Don't overdo it, just lighten the load a bit. This will greatly reduce the torque needed to turn the nipples.
I wish i had heard that 3 years ago... I have scraped/rebuilt so many wheels due to this problem.