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Want colored galvanized sheet metal

Hello all, thank you for taking the time to look at my question! I have some galvanized steel sheet metal (approx 22G?). They are 3'x4' sheets and will be installed indoors as part of an artistic and functional air diversion design. They will be regularly subjected heat from 90 °F up to 200 °F. My question is regarding how they will look and last; I would prefer to keep some (if not all) of the "metal look" (i.e. I do not wish to paint them a solid, flat color). Is there a process that could provide an interesting color or patina to the zinc galvanization? I realize that the galvanization itself is a sort of patina, but I am attempting to steer the look away from the classic galvanized "street lamp" look and more toward something a little more colorful (though actual color is not pertinent).

If a color shift is not possible, is there something I can/should do to protect the zinc from further oxidization? Perhaps a clear coat?

I appreciate your time!

Thank you in advance!

Logan Needham
student - Sparks, Nevada, USA
2005

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Hi, Logan. Galvanized metal is steel that has been hot dipped into molten zinc -- so the surface is zinc. Galvanized ductwork and vent stacks are used all the time, so the temperature should not be a problem.

But zinc does not get the colorful blue, green, and brown reaction products that copper and brass do. Paints and lacquers will rarely stick to it and will peel off instead, further limiting your options.

We have a few topics on line here suggesting that wax is a good finish for galvanized surfaces. Putting all this together, although I haven't tried it myself, it sounds like a Rub'N'Buff [affil links] antiquing finish might be a good answer.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey