Originally Posted by
merziac
Wow, never had to cut, drill, grind, saw or otherwise butcher any cups, ever, which is key when the offender is odd, rare or otherwise should be saved if possible which imho is always. With my method they always come out, never damaged a frame, cup, tool or otherwise. Only been doing this for about 50yrs so maybe I haven't seen it all.
The hot screwdriver sounds like a pretty good idea.
I accepted a early 90s Bianchi frame with a broken spindle as a partial trade for another vintage frame. The owner had taken it to a number of shops who declined on the work, declaring the frame toast. Like you, I had never met a BB that I couldn't remove with a little patience and intelligently applied force and since the frame was otherwise really nice, I was happy for the trade ... had I only known that I was up for over 10 hours of work to get the thing out. I started with penetrant, gentle heat, and sufficient time to let it soak in. No go. Tried a pipe wrench on the exposed NDS cup threads. No go. Put the DS cup in a big bench vise and used the frame for leverage. No go. I finally decided that the only way that it was going to come out is if I cut radial reliefs through the cup almost down to the shell threads. The problem was that the spindle needed to come out first. I drilled a circle of holes around the spindle on my drill press and then used a dremel tool to cut the metal between the holes, which allowed the spindle to come out. Then it was just a bunch of grunt work cutting radial reliefs in the shell, first with a dremel and then with a hacksaw blade as I got close to the shell threads. I have to say that the cups are hardened especially around the bearing surface so the going was slow. After making the radial cuts I was able to use a punch to collapse the cups slightly inward allowing them to be removed without damaging the shell.
Although I was ready to give up a few times, I am glad that I persevered. That frame is now one of my favorite bikes (650B conversion). Since then, I have gotten 2 other free frames with rust welded BBs. Neither of them responded to 2 hours of work (now my guideline for this sort of thing) so they went for scrap. The lessen in all of this is to use anti-seize or grease for any BB installation. I am not sure that removing the BB every few years would be necessary if you grease the threads, but it's easy enough to do.
To OP: sorry for the slight diversion. Glad you found success.