Praise be to @danson67 who completely fixed my frame through his method explained above!
See photos of grinding out the remaining damaged thread using this tool, then inserting the Italian thread, then the finished result! All done in around an hour.
Thoroughly nice chap, and nice to admire...
Hiya, it looks like the thread has worn too much for this trick. I've managed to persuade @danson67 to have a look at it, think he will insert an Italian thread. Thanks anyway!
Hi @danson67, I found this page through google. Damaged my BSA threaded shimano bottom bracket racing down Cadair Idris, and was told by my LBS that it is impossible to fit a threaded bb cup with the damage there is now. I quite like this bike, and don't really feel like getting a new one...