Originally Posted by
southpawboston
I'm building up a new frame. It's never had a BB installed. The BB threads appear to have been tapped before media blasting and powder coating, and the shell faced after. There is debris along the threading making it difficult to thread the BB in.
Without going to an LBS or buying a proper tap set, is there a DIY solution to just chasing the threads?
If you have an old BB shell and a bench grinder you can probably grind some grooves into to to make a sort of tap to clean the threads out ??
Have a look at a tap to see how the flutes are ground, and try to duplicate that to some degree, you could probably use a Mill bastard Nicholson file too if you do not have a hand grinder with a cutoff wheel or a bench grinder.
Bill