Help with Bottom Bracket removal

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I have an old track bicycle frame that has a splined Campangnolo bottom bracket. The splines on the cups are all gone, stripped off so the insert/removal tool won't fit. This probably happened when the frame was repainted and paint got on the threads making it difficult to adjust so they just stripped it. Any ideas how to remove these cups? My only thought is to weld on large nuts to the face of the cups and put it in a vice and turn the whole frame.
 
My only thought is to weld on large nuts to the face of the cups and put it in a vice and turn the whole frame.
That is probably what I would do.
 
That is probably what I would do.
I'm worried about the brazing on the bottom bracket lug. I don't know if welding would melt or effect it. I was wondering if TIG would be the way to go? I don't have aTIG machine. It's a really special frame, but like all old stuff has problems. It's been hacked on a little, but nothing I can't fix, except maybe removing the BB.
 
I'm worried about the brazing on the bottom bracket lug. I don't know if welding would melt or effect it. I was wondering if TIG would be the way to go? I don't have aTIG machine. It's a really special frame, but like all old stuff has problems. It's been hacked on a little, but nothing I can't fix, except maybe removing the BB.
Tack a piece of flat bar across it and spin it out. brazing requires a decent amount of heat. I don't remember the temp but you need to get steel to a dull red to melt brazing rod from what I remember.
@jamesdart suggestion is good, welding flat bar will mean you are only heating two small areas too, a little heat through the cups will help free it up too.
 
Tack a piece of flat bar across it and spin it out. brazing requires a decent amount of heat. I don't remember the temp but you need to get steel to a dull red to melt brazing rod from what I remember.
Good idea, the bar will work on one side, the other is recessed and it might be a little harder to do, might mess up the threads with splatter. I might have to have a pro do this as my welding is OK but I want a good penetrating job. I have a Miller 240 volt AC stick welder and a Miller 140 MIG welder. I have no TIG, but you make it sound like I don't have to worry about that. I'll take it to a fab shop to see what they say. Thanks for the excellent idea.
 

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