"Grant Erwin" wrote in message
...
I got a lot of really old but almost entirely unused Airco torch tips
today.
Many are of a kind I've never seen before. They are *old* new old stock,
maybe
WWII vintage judging by other items in the same lot. They came in original
cardboard tubes which weren't airtight, and they have almost all
tarnished. I
don't care if a torch tip is shiny or not, but I'm trying to read the
number off
the things, and polishing 49 tips with Brasso would be tedious. I'm
wondering if
there isn't some passive method like an overnight soak in citric acid or
maybe
vinegar and salt that would clean off the tarnish safely.

Anyone?

Grant Erwin
Kirkland, Washington

Copper will not dissolve in sulfuric acid, but oxides do. You can restore
them to almost new looking condition by pickling them in such an acid.
Heating the acid will accelerate the cleaning action. (Tried method, not
something I read).
Don't use metal vessels. Wash well with clean water afterwards. An old
auto battery might be a source of acid, assuming you can't find it
elsewhere. Protect your eyes and hands. Yeah, I know, you already know
that. :-)

Hope this helps-----that's a lot of polishing otherwise.

Harold