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How to "stain" and/or paint galvanized sheets for outdoor resistance for decades

 

On GALVANIZED sheets, I want paint and/or "stain" the surface and keep at some spots the aesthetic effect of the metal-silver coloration and mixed with different transparent (almost) layers colors. My purpose is for making "special hand made shingles" exposed permanently to the variations of the weather(especially tropical with sun rays, and can resist to the discoloration for decades without peeling, (yellowing or very few) and be 100% waterproof.

To obtain a better adherence (and also for personal aesthetic effect) I want to create a "subtle texture" on the surface of the metal by overpassing a metal sandpaper for my personal artistic effect. For the last coat, I'm ready to spray or brush the best clear coat quality or according to yours recommendations changing for a another method. For more protection, I'm also ready to have a program of maintenance (example: each 6 months apply a wax or similar bests products that we found for the car). My question is: What kind of paint and procedure/method a need to have for a permanent success.

Thank you.

Andre Coderre
- Riverdale, North Dakota

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First of two simultaneous responses --  

It's always nice to have a wish list, Andre, but I don't think there is a technology based on galvanizing that will come close. It's hard to get adhesion on galvanizing, requiring a zinc phosphate conversion coating process that will ruin the metal look of the galvanizing.

How about nickel plating the shingles, then applying e-coats of various shades and translucencies, for the best brightness? Alternately you could probably zinc plate them before the e-coat? The biggest issue I see is that if it's not factory-applied e-coat on a fresh plated surface, you are going to have severe adhesion problems unless you use a pretreatment that destroys the metallic look. Good luck.

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

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Second of two simultaneous responses --

Dear Andre,

I would seek out a manufacturer who advertises a "lifetime finish". Let's all hope that they will still be around in "decades" when your coating fails, and will have a smile on their face when they replace it.

Good luck,

Jake Koch
G. J. Nikolas &Co.,Inc.

Bellwood, Illinois