Originally Posted by
arex
I did this on a Raleigh Sports, worked out very well. Used the Raleigh cups, a 73mm Shimano JIS square-taper spindle, and 6mm grade 25 ball bearings. Went together perfectly, no fiddling involved.
Originally Posted by
scarlson
Ohh, that would be such a pain to do on the lathe!! Difficult fixturing. And no second chance if you mess it up and cut too deep or the work shifts in the chuck!
I would rather save the time and buy Phil Wood rings. You don't want to spend the money on a whole Phil Wood cartridge, so you just get the rings and use a Shimano UN300. It will work. They are the same diameter.
I have used the Sunlite threadless (came with a frame with stripped threads). It kept loosening up on me. I eventually welded and retapped.
Other things you can do include using the existing cup and cone system but putting a square taper cup and cone spindle in. They normally work with the Raleigh cups.
Sheldon Brown has a thing about this on his site.
Thanks! I would be happy to use a Phil Wood bottom bracket, but they're sold out of all of the spindle lengths that are even close to the 118mm that I need for my crankset. The Phil cups and UN300s are both available, though, and I think I'll give it a shot with these.