Is it possible to paint over anodized aluminum, does it need any special prep work?
Can I paint over anodized Aluminum?
-
-
No you can not
The finish need to be removed -
No you can not
The finish need to be removedCould I sand blast the part?
-
Depends on the part
I don't remember what the powder coater used - I think it was some sort of drain cleaner that etched the finish.
I wasn't there when they did my parts -
-
-
Depends on the part
I don't remember what the powder coater used - I think it was some sort of drain cleaner that etched the finish.
I wasn't there when they did my partscould it be they used regular etching primer?
-
Is it possible to paint over anodized aluminum, does it need any special prep work?
.
"Anodizing is the best possible surface for paint adhesion. No special primers or anything like that normally associated with painting aluminum is required. Bare aluminum is highly reactive with air. It doesn't matter what you do to get the surface bare, chemically or mechanically, because it immediately begins to reform oxide to protect itself. An anodized surface is non-reactive, or inert, in atmospheric exposure. That's why its appearance stays substantially the same over time. Because it is inert there's no need to apply any chemical or primer whose purpose is to convert the surface from reactive to inert. Also, the method of "growth" of the anodized surface leaves it somewhat porous on a microscopic basis, so it has ideal properties for letting the paint "grip" the surface. As an example of how well anodized aluminum holds paint, all pre-painted architectural sheet aluminum is first anodized and then painted with no primer of any kind between the surface and the topcoat. You can typically take a piece of this painted sheet, bend it in a brake, and fold it flat on itself like a hemmed edge, and the paint will remain intact."Paint Adhesion to Anodized Aluminum?
Just make sure it is super clean ... anodizing then coating is a common practice to get aluminum parts to pass salt spray testing...
. -
Anodized Aluminum I usually sandblast the finish off... it's very quick and easy. Then clean the part, bake in the oven at 250 for 15 min, let cool and clean with acetone. Aluminum is very dirty and baking takes that to the surface. You need a self etching or epoxy primer to prime before paint.
I have had no luck sandblasting powdercoat! I will dull it in the blaster, clean real good, use an epoxy primer and then paint. The epoxy primer is the key here as it has great adhesion.