This is probably a question for the Bicycle Mechanics forum but 99% of the time I read Classic & Vintage so here is the problem/questions:
I recently started rebuilding a 1975 Holdsworth and in taking it apart I find that the chainwheel side BB bearing race has been tack brazed to the frame. Why I don't know, but I suspect that perhaps someone earlier had stripped the threads and the tack weld was a way to keep the race in place.
My questions are: Should I file the tack off and remove the race? Can the threads be repaired? Leave well-enough alone? Your comments, suggestions, and recommendations will be appreciated. Thanks.
Skip Magnuson
Spokane, WA

If the bearings were in reasonble shape I would leave well enough alone. Taking it apart may result in a ruined frame. Roger

Hmmmm...that's a tough call, but i agree with Roger that if the fixed cup is in good shape, leave well-enough alone. It would sure eat at me, though, if it were mine. If the cup is bad, or gets bad enough, or you just can't stand having it tacked in place...you can always remove it and if the threads are bunged up (beyond repair) have the BB shell reamed and retapped for Italian. If so, I'd opt for a Phil BB with Italian rings and that'll last "forever".

Italian is the biggest in diameter so is the last resort. Bad time to ask, but could the shell be cracked?
Any signs of distortion? Holdsworth in that era hearth brazed the BB so the whole shell got heated to red hot, then the brass was added, the heating can and could anneal the shell making it malleable...

Agreement here, too. There's been lots of times when I've worked on something long abandoned that the chainwheel side cup is absolutely immoveable - to the point that I've done a long dowel with cleaning material on the end that I can soak in kerosene and scrub it down while still in the bottom bracket. And I've gotten very good at laying in a layer of grease under the same circumstances.

Not elegant, but it work well enough.

At least your Hetchins BB shell wasn't threaded backwards. One of Jimmy Thompson's 24 bikes has the fixed cup on the LEFT side of the BB shell.

If the bearing races are reasonable, leave well enough alone and reassemble with new ball bearings, preferably loose, rather than caged.

Thanks Roger Rhenning, Unworthy1, Repechage, Sykerocker, & John E.
Just the feedback I was looking for. At first inspection, the race looks ok. It does have loose bearings which I will replace. John E, I understand from your post that the Holdsworth and Hetchins right side shell has right-hand threads - is that correct? Thanks guys, I'll let you know how it all turns out.
Skip

I can't speak for John E., but I gather he was refering to an anomaly: neither of my 2 Holdsworths have "backwards" BB threading, that is they are the usual situation where the RH or fixed cup has LH (or reversed) threading and the LH or adjustable cup has RH (or normal) threading.