Nipple breakage

Tom Sherman wrote:

Why are nipples brass instead of stainless steel?

Stainless-on-stainless threads gall like crazy wherever lubrication
fails. Brass on ferrous metal behaves relatively well even without
lubrication. There are some alloys that might make stronger, better
spoke nipples than yellow brass-- Monel comes to mind-- but stainless
would probably cause more troubles than it solved.

Chalo

On Aug 8, 10:22*pm, Chalo wrote:
Tom Sherman wrote:

Why are nipples brass instead of stainless steel?

Stainless-on-stainless threads gall like crazy wherever lubrication
fails. *Brass on ferrous metal behaves relatively well even without
lubrication. *There are some alloys that might make stronger, better
spoke nipples than yellow brass-- Monel comes to mind-- but stainless
would probably cause more troubles than it solved.


I second this explanation. It is also true that brass
behaves better than aluminum - this probably has
something to do with ductility, ultimately it's a
tribology issue.

Another example that some of you may be familiar
with are the filters that you screw onto camera lenses.
These have a large diameter thin fine-pitch thread.
Many filter rings are aluminum and when you screw
these onto an aluminum lens barrel, they can gall
or get stuck on. There are a few (pricier) brands of
filters that use brass rings and these have fewer
problems with galling or sticking.

Ben