tcpasley

I picked up an otherwise nice used wheel that has crumbling aluminum nipples. I first noticed a spoke with the nipple head snapped off and the barrel seized on the spoke threads. I then tried to loosen a couple of adjacent nipples, which just crumbled. The wheel was apparently ridden on salted roads or lived at the beach. Other nipples proved to be seized. I'm hoping to replace all the nipples with brass, but it looks like it won't be easy.

Does anyone have any tricks to share for removing seized nipples? If I can crumble them all and snap off the heads, maybe I can crush the barrels in a vise. I may have to cut a notch in a screwdriver (sort of the reverse of a spoke driver) and try to snap off the heads from the spoke ends.

I don't want to cut out the nice old 2.0/1.5 Wheelsmith double butted spokes, since they are in fine shape, as are the Open Pro SUP rim and the Dura Ace 7700 rear hub. I don't want to spend $40+ to replace them.

Any advice is greatly appreciated.

Bill Kapaun

Use a vise grip pliers.
It'll strip them off pronto.
Use the right amount of tension and they "peel" off.

Kimmo 

It's easy to just to rip off the section with the flats, probably leaving your vise grips uncomfortably close to the rim, which I'm sure you'd rather not scratch...

I like the spoke driver idea, and where that fails, you can mostly drill out the head, maybe finishing the job with a punch when you're >90% through. You can probably crack off any remainders that won't unscrew by smacking them with a hammer on an anvil. A bit of oily scourer action to clean up the threads, chase with a lubed nipple.

Crankycrank

Try getting all the spoke nipples off from 1/2 of the rim and this should give the spokes on the opposite half some slack to push the nipple heads out and grab them with vise grips or pliers reducing the chance of damaging spoke threads. Not a magic solution but it helps a little.

ft3safety

I know you don't want to but I'd cut the spokes and just replace them. You can get double butted spokes for around $0.80 each. If the nipples are seized who knows how worn out the spokes are as well. For me it's better safe than sorry.

3alarmer 

...this is the route I would go as well. While it's rue that in a galvanic corrosion situation, most of the corrosive effects will sacrifice the aluminum alloy in preference to steel, the threads on stainless spokes are pretty fine. It's almost impossible to clean them up to the point I'm satisfied using them to rebuild a wheel. If you know of someone with a spoke threading machine, like the Phil Wood one, local to you, you can save the spokes, shorten and re-roll the threads for a smaller wheel project.

adipe

i'm not sure what penetrating recipe would be best for this. some use 50/50 ATF+acetone as a penetrating agent. you could first try with acetone+paraffin. the acetone will decrease viscosity and should evaporate later on. paraffin is a very good electrical insulator. you better leave it for some time and possibly re-apply before using the spoke key for best results. hitting the spokes a bit (with some plastic pen etc.) - just to make them vibrate on the nipple interface - could help to make small cracks on the corroded aluminum surface of the nipples so that the penetrating agent will work it's way. see if you can get the spokes to momentarily drop as much tension as possible when doing this - you could pull the rim sideways, so that some spokes will gain tension and others will drop tension. mounting some tire and pumping it up to almost maximum pressure allowed will also help spokes to drop their tension. be careful though that rim has it's limits and too much pressure can make the tire usafe to ride (becoming prone to punctures if inflated to max pressure).

not sure if your rim would be safe if using ATF, that's why i'd say to use paraffin+acetone first.

and one more thing: DON'T EVER use aluminum nipples again - unless you don't care about long term reliability - and also use bolt grease/paste on both spoke thread AND nipple contact with the rim's eyelets. if the rim does not have eyelets then it is even more important to use the right lubricant for the job. don't use regular (brand) chain lubricants but rather make your own homebrew. you could mix some petroleum paraffin (iso-alkanes, alkanes, cycloalkanes - avoid candle wax) with some quality polyurea grease. from what i've head beeswax is good for the job (instead of the proper petroleum wax that should not contain too much straight alkanes) though a bit pricier but you should mix it with something that will keep it from oxidizing (additives in greases). avoid lithium greases as they don't last very long.

brass nipples can also seize and they should be lubricated.

aluminum nipples are only good for competition wheels in order to shed some grams. also harder to build the wheels with them (CoF will be higher), not worth using them long term.

Kimmo 

Contrary to popular opinion, spokes can well outlast rims. As long as the wheel has had sufficient tension (more likely the lower the spoke count), the spokes won't be fatigued.

If the threads are severely crusted up, you could try cutting a slot in a brass nipple with a Dremel to make a die, which I suspect would be more successful at cleaning the threads than a thread roller.

adipe

use heat as a last resort. aluminum has a higher thermal expansion than steel.
cold worked steel (spokes) will lose it's strength if heated too much; the rim (aluminum alloy - as it is heat treated) is also vulnerable to lose it's temper.

tcpasley

Thanks to everyone for all the great advice. I was able to get a screwdriver on most of the nipple heads and either free up and loosen the nipple or snap off the nipple head. Some nipples even survived the spoke wrench and can be threaded off.

I'll have to find my vise grips to crack off the remnant spoke barrels, The worst few that wouldn't budge will get pushed back through the spoke holes and demolished as Crankycrank suggested. As the son of a mechanic ("Boy, don't ever use pliers on a bolt or nut."), using vise grip pliers on threaded parts is not the first thing that pops in my mind, but it's good to have the "vise" capabilities.

The rim has double eyelets, and I found my bag of sturdy Sapim brass nipples, so I should have no trouble rebuilding a long-lasting wheel. I have a Mavic rim for the front that's a good match, and I'm looking for a Dura Ace 7700 front hub. I expect to have a wheelset that might outlast me.

Crankycrank

Ohhhh, I should have emphasized that the vise grips aren't to be clamped on with crushing strength, just grab the nipple head with enough force to turn it. Hope it works out for you.

tcpasley

No problem. I have just enough common sense left to keep from going gorilla on things. I can't put too much twist on the spokes, since they're 2.0/1.5 DB and can't take it like a straight gauge spoke could. If the nipples are too corroded to turn, that generally means they'll be brittle, and I can probably peel the barrels off as Bill Kapaun suggested above.

Gresp15C

Perhaps squeezing on the nipples with a pliers will crack them off.