"Steve" wrote in message ...
: I was removing some hose clamps from the hoses to my head. (minor leak).
:
: The hose clamps were bleeding rust where the seeping sea water was running
: over the them. These clamps had only been exposed to the marine enviorment
: (in the head) for one year..
:
: I checked the markings on the screw housing and it said IDEAL All
: Stainless.. I grabbed a magnet and sure enough, the screw is magnetic. Looks
: like stainless, not zinc or cad. plated, but it is some grade of stainless
: that is not only magnetic, but rusts.
:
I've heard that there's no such thing as truly 'stainless' stainless
steel - it a treatment of the metal that'll retard corrosion for a good long time.
They tell me that as far as magnetic testing goes - grab your all-stainless kitchen
knives and note that they'll all stick to the magnetic knife holder, and left to
they're own devices will rust, too.

I can't for the life of me remember how to make steel stainless, or the
difference between stainless that'll stick to a magnet and stainless that
won't (believe it or not, I did know once...).

I'm kinda looking forward to someone playing metallurgist on this thread
and filling in the blanks.

Dave