Originally Posted by Iowegian

I've heard you can use the Phil retaining cups with some old Shimano cartridge BB's (eg UN-72). There are probably other cartridge BB's that would work as well, but as you probably know, the Phil cups aren't cheap.

The biggest problem I see with switching BB types is the different shell diameters. French and Swiss are 35mm, Italian 36mm, ISO 1.37 inches, Raleigh ?? Brazing new material and tapping new threads could be done but changing a 35mm shell to something else would be tougher.

There are also 'universal' BB's that don't have threads but wedge themselves into the shell. I haven't heard many good things about these except that if all else fails, they can be used to salvage an otherwise useless frame.