What's the best way to paint aluminum so paint will stay! ? What primer will stick the best?
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What's the best way to paint aluminum so paint will stay! ? What primer will stick the best?
My dad told me that aluminum painting is a type of rust and you add pigment to the rest and that's how painting is done
You can get aluminum specific primer at any auto parts/ auto paint store. It just comes in an aerosol spray can and is made by rustoleum as well as krylon and others. The primer is usually a dull green tone. Just make sure it states that it is good for aluminum when you select it. Make sure your metal is perfectly clean and dulled up by fine sanding to give the primer some good bite. After a couple of coats and drying, then you can paint with the finish of your choice using automotive/aircraft/or outboard engine marine grade paint.Quote:
Originally Posted by lilwhirlwind
You can get aluminum specific primer at any auto parts/ auto paint store. It just comes in an aerosol spray can and is made by rustoleum as well as krylon and others. The primer is usually a dull green tone. Just make sure it states that it is good for aluminum when you select it. Make sure your metal is perfectly clean and dulled up by fine sanding to give the primer some good bite. After a couple of coats and drying, then you can paint with the finish of your choice using automotive/aircraft/or outboard engine marine grade paint.Quote:
Originally Posted by lilwhirlwind
Now what primer mainly does, is it provides a medium for the finish (often acrylic) to stick to. Primer can be thought of as that like the Gesso used on an artists canvas. A primer for metal often has an etching agent in it that makes it get into the metal surface and stick. The filler in the primer has a smooth yet dull texture that can act somewhat as a shell of which the acrylic will etch into leaving the pigments permanently binded onto the finished surface. Acrylic itself is actually a clear gel. The pigments are added to make a paint. Auto and utility paints are made from light bodied gel (like a liquid). Medium bodied water soluble acrylics are used by artists. Sometimes we would just by a medium or heavy clear gel for impasto (raised texture brush strokes) and add our choice of natural earth pigments for portrait painting. You can actually sculpt with heavy bodied acrylic! This material was invented in the early 1900s to use for military equipment and industrial applications. Artists acrylics are water soluble though, whereas what you will use is to be thinned and cleaned with a auto paint thinner. I have been a Plein Air artist (French Realism/ and American Impressionism styles) for many years in case anyone is scratching their heads! LOL!!
Quote:
Originally Posted by champ20B
Lol, thanks for the info! That's definitely what I needed to know lol. I think the primer your thinking of is called zinc chromate. I was told you couldn't sand it though?? I would think it would be fine to sand.
You just need to lightly rough the bare metal and clean it well. Then you put on the primer afterward. Don't sand the primer because it will give a texture that will give your top coat a good grab. Apply several coats of your auto enamel, wet sanding between coats. You need fine 1000 wet/dry paper from an auto parts supply store and keep a bucket of water to wet the paper as you lightly dull each dry coat to a satin finish. Wipe it off clean and let it dry then put on another paint coat. After you apply the final finish painting completely, and let it cure, you can smooth it if it has "orange peel surface" by wet sanding. Then buff it out shiny with fine compound and a chamois cloth or a small buffing wheel. Your local paint supplier can tell you what grades to use. Usually, just start with a heavy compound machine glaze and work to a fine polish compound. Don't over-rub through the paint though. This will give you a shiny mirror finish that is easy to clean and keep waxed on your motor. Its hard labor, but as for results,You'll really like it!Quote:
Originally Posted by lilwhirlwind
I haven't tried this yet but I heard that you can wipe down with vinegar and that causes a reaction that will allow the paint to stick.
id be afraid to try that! best way is to use chromate vynil wash (etch primer) followed by a sealer or primer depending if you want to sand imperfections out, you can also use a chromate epoxy to skip the 1st step,, or any expoy for aluminum followed by a topcoat urethane auto paint with no sanding but the epoxy and topcoat you would need a compressor to spray, the vynil wash sticks better if you mix and spray it vs a spray bomb tooQuote:
Originally Posted by 84 centurion
Aluminum "rusts" instantly when the surface film is removed. The result is a slippery coating of Al oxide that HAS to be removed or the paint will fall off. The primer supposedly fixes this, but a good etchant (West Marine and elsewhere) sets up the surface properly.
Did the entire bottom of a 32 foot aluminum boat that way and the paint is still on.
Jeff