Jack Romans noted >> Following some CR-listers suggestions for an alternative method, I cleaned >> BB threads and properly re-installed cups. Due to thread damage, the >> biggest problem encountered was starting the cups square with the BB, esp adj cup >> in my case. Once this was accomplished, running cups in-and-out a few times >> while cleaning-out steel splinters in-between did the trick. I think that >> if I had attemped to re-tap as I originally thought, it might have been very >> difficult to keep my taps square which would have resulted in further >> damage. If I ever get the chance to use my expensive BB taps, I'll be especially >> wary of crossed starts!
And Chuck Hoefer responded:
The method you used is great. <snip> The lockring makes a great guide to help you get the cup started correctly. Just screw it on almost all the way on the cup's threads and it will be a fine sight reference for a straight start. +++++++++++++++++++++++++++++++++++++++++
And remember that certain inexpensive off-topic cartridge BBs have left hand threads, useful for starting the right side cups with English thread. Of course, as a true vintage-ista, I only know of such things by rumor.