Jack- you're pretty much answered your own question. After common methods fail, including augmentation with liquid soaks, you're left with destructive ones. A die grinder used to grind down/through the frozen and broken cup is the last resort. Some times only one ground down section will be enough to let the cup 'collapse" inwards, breaking the bond with the shell. Some times two opposing sections need to be ground down.
This is very much like removing a stuck free wheel, except the access is a lot more of a PITA.
Todd- Please trim your replies!!! The needless volume of the list digest in your posting was more then 2/3 of the current digest and not pertinent to your reply. Thank you.
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Message: 9 Date: Wed, 28 Oct 2009 01:46:36 -0400 From: <Carb7008@cs.com> Subject: [CR] Broken Fixed-Cup Removal at SBK To: <classicrendezvous@bikelist.org> Message-ID: <d50.5c223c75.381934bc@cs.com> Content-Type: text/plain; charset="US-ASCII"
Here in Sacramento we have a volunteer bike-biz catering to folks. A gentleman came-in tonight with a loose crank,which upon removal of BB, the fixed cup had circumferentially broken in-two such that about 3/4" of the inner portion of cup remained threaded in the shell about 1/4" deep. Every effort to remove, including un-screwing, cutting with hacksaw, notching with file, prying with screwdriver, failed to remove hardened (why do you think they call them "fixed"?) race.
I doubt a cold chisel, which we didn't have, would have cut-through. A Dremel tool may have worked if we could have gotten the cutting-wheel inside the BB shell. Needless to say, the gentleman walked his OT bike home. Any ideas short of torch or liquid nitrogen embrittlement?
Jack Romans Sacramento, CAlifornia
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Message: 10 Date: Wed, 28 Oct 2009 00:18:36 -0700 From: Todd Teachout <thteach@sonic.net>
Andrew R Stewart
Rochester, NY