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  for Metal Finishing since 1989
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Coating for water-based sign paint

Would anyone know of a product that would protect an airbrush paint application from a harsh environment. Something like a clear coat that would dry to an extreme hardness level? Is there such a product? I have tried automotive clear coats but they do not seem to have the hardness that we are looking for.

John C. Allen
fishing lures - Syracuse, N.Y., USA

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If automotive clearcoat did not give satisfactory results, I am quite surprised! Perhaps the auto paint supplier did not give you the right stuff. A good polyurethane clearcoat that is not part of a wet-on-wet base/clear combination should provide excellent results. We have used even one of the generic (cheap) clears that gives great hardness, excellent gloss and outstanding durability. Since this is a plural-component polyurethane material, you MUST use either a supplied-air respiration system or perform expensive testing to show that isocyanate levels do not exceed allowable (very low) levels. And as with any respirator program, check out OSHA requirements about physical exams, etc., for all respirator users.

After all that, maybe you'd consider outsourcing...

Michel Moninger
- Sarasota, Florida

You may want to try a 1 component moisture cure urethane. They are available in water white clear and provide very hard surface.

Gordon Vidt
- Newark, Ohio

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I painted a 56' x 12' mural with airbrush about 6 years ago. It was on a wall outside a cafe in Boston so I coated it with a "graffiti-proof" epoxy or urethane. I can't remember the name of it but it cost about 60.00 a gallon. It has not had any problems at all from sun, weather, age, nor graffiti all this time. I have been really pleased, finally, with the result of such a coating.

Rose Kirby
- Coxsackie, N.Y., USA

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Dear Friend,

I know that a chemical resin company in Georgia produces an epoxy type substance (you have to mix the two substances and then apply it). It sets up perfectly clear and is not a "wet coat" --- so you get the protection you are looking for. After re-staining my deck I did some research and found it.

Ray Greco
- Conyers, Georgia
2007