Originally Posted by
zukahn1
I very nice 12inch a adustible wrench will bust most BB's and hard work on nearly anything.
The flats on a fixed cup are often too shallow for that... not that they don;t come in handy for other jobs.
The Shelbroco tool works really well when you need to remove a fixed cup that resists extraction although in practice, one should just leave them there when they are servicing the bottom bracket.