From: rjt@cbnewsl.cb.att.com (ross.j.thompson)
Subject: Re: Bottom Bracket woes
Organization: AT&T Bell Laboratories
Distribution: usa
Date: Wed, 12 Aug 1992 19:41:48 GMT
Summary: Advice for removing seize "adjustable BB cup"

In article <1992Aug12.121224.23524@cs.hw.ac.uk>, sfleming@cs.hw.ac.uk (Stewart Fleming) writes:
> 
> 
> Does anyone still have the list of recommendations of what to do with
> seized bottom bracket cups ?  There was a thread going round here a while
> back which I didn't save.
> 
> The problem is this :  I wanted to get a new sealed BB fitted, so I took
> my old bike to the shop for fitting.  When I collected it this morning,
> I was told that the adjustable cup had seized in the threads and
> could not be removed.  Now, this might be OK, if the "mechanic" in the
> shop had not taken a hammer to the adjustable cup and deformed the
> slots where the remover tool fits.  No normal approach is ever going
> to shift that cup now.
> 
> If I can't get the BB removed,then I need a new frame.  One of the extreme
> methods discussed in this newsgroup a while back might help get the cups
> removed.  Alternatively, I need some advice as to the liability of the
> shop in not carrying out the repair competently.
> 
> Thanks for any help or advice,
> STF
> --
> sfleming@cs.hw.ac.uk                        ...ukc!cs.hw.ac.uk!sfleming
> "He not only moved the goalposts, he dug up the pitch
>    and took the ball home as well."


Stewart,

I went back an reread your original post to make sure you were talking 
about the adjustable BB cup specifically.  From some of the advice you
received from other posters, it was clear that there was some misunder-
standing about which cup you were having difficulty with and the state
of the BB.  Assuming that it is the adjustable cup, the failed attempt
by the "shop" has been unable to disassemble the bottom bracket at all
which means that the spindle and bearings are still in place.  If this 
is correct, I think I have suggestion of how to free the adjustable BB
cup using simple tools but the adjustable cup itself will be sacrificed.
From your description of what the local shop did however, the sacrifice
has already been made.  By the way, I think they are liable, but I doubt
you'll get much satisfaction from them, particularly in light of their
earlier attempt at "service."  I certainly would not risk new components
in the hands of those people; you may have already seen their best!

Begin by removing the lock ring from the adjustable cup if you haven't
done so already.  Soak the exposed threads liberally with penetrating
oil or WD-40.  Repeat several times.  With a small cold chisel, go 
around the perimeter of the exposed part of the adjustable cup lightly
taping with a machinists hammer to help loosen the remaining threads.
The exposed threads will hold the blade of the chisel.  Now take a fine
pitch (32 teeth per inch) bi-metal hack saw and cut two "flats" in the
exposed part of the adjustable cup on opposing sides of the diameter.
The bi-metal blade is preferred for wear and accuracy and the fine pitch
of the teeth should help start and cut straight lines.  Cut into the face
on each side first and then cut in radially to intersect. You should be
able to make a shoulder surface about 25-30mm wide and 6-7mm deep if you
cut flush with the edge of the BB shell.  You can square the shoulder a
little bit with a file after cutting.  

With the flats cut, clamp the flats in a heavy bench vise with smooth jaws.
Using the entire frame as a lever arm, unscrew the adjustable cup from the
frame. Beware that if the BB shell starts to deform you should stop and
repeat the lubrication and loosening steps again.  Note that this technique
can be used equally well to remove the fixed cup(it already has flats) if it
is also seized or just properly tightened.  If you are successful at removing
both the adjustable and fixed BB cups, I would recommend having a frame-builder
retap the BB shell before installing the new BB just to be on the safe side.

Good luck.  If you commit to trying this, go slow and take your time
with the saw.  Patience will be rewarded with success.

Ross Thompson
AT&T Bell Laboratories
Whippany, NJ

Newsgroups: rec.bicycles