I have just removed my cottered bottom bracket and would like to reuse the cups and ball bearings. Can i just add a cotterless axle of the right length instead of buying a sealed bottom bracket? I'm figuring i should have an axle of the right length some where.
Is it possible just to swap axles?
Thanks

You May be able to find some loose ball replacement axles , Note the word MAY ..

Check with your local bike shop .. . QBP is the big wholesale importer in the US,
many shops buy from them.

I might have one but if not my local bike shop has boxes of old and new items.
But it is ok just to change the axle? It makes no difference if using a cottered or cotterless.
Axle thickness is the same and same size ball bearings?

Yes.

Ok great thanks.
One last question! I noticed the cottered axle is a lot longer on this peugeot then a another peugeot with a cotterless axle.
Is it normal that cottered ones are longer. Would i match the length with the other peugeot that i have because the bottom bracket shell on the frames look about the same.
PX 8 cottered PX 10 cotterless. I had a PR 10 and it was an 118mm stronglight axle. Would these vintage peugeots use the same length axles?
Sorry for all of the questions!

A bit suscinct but this is correct. Years ago I did exactly what you propose for a friend's old Raleigh since we couldn't find suitable cups with Raleigh's proprietary threading. I just exchanged the cottered Stronglight spindle for a proper length SR square taper spindle and crank and kept the old Stronglight cups. I did use new bearing balls.

The required axle length is determined by the crank you use and must be long enough so the chainrings don't hit the frame but not so long as to give a poor chainline. Square taper axles will usually be shorter than a cottered axle.

Many thanks for your help and much appreciated!
Thanks guys