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Interlux's website didn't say anything specific to aluminum. The hood is already painted, just needs some bondo work, primer, etc. I guess I'll give them a call when I get around to it. Thanks

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As the other contributor noted... aluminum is more of a pain for surface preparation - and probably double so for aluminum aircraft surfaces.

And in the aircraft world, I would assume that surface preparation for a high speed - high altitude aircraft is more complicated than that for the slower, lower altitude personal aircrafts. So even in avionics there are differences. As a funny aside to this topic, I remember that the US P51 Mustang aircraft was sent to battle during the Second World War without camoflauge paint - and with its aluminum body in its natural shiny metallic look. They claimed they didn't need to paint the P51 because it was so faaaaaaaaassssssssssst that it didn't need to rely on stealth or camoflauge in battle. But maybe they also were encountering paint adhesion problems back then

My only experience with paint on aluminum is with a Jaguar XK140 C-Type roadster. The C-Type was the racing version and they used aluminum on the doors to light the car. When paint got chipped on that door... I was quite surprised by how shiny the underlying aluminum was. We would dab a little paint to mask the chipped paint... but it seemed that it just couldn't adhere securely to it for any length of time.

As you will have noted from that article contributed by the other user, the aircraft boys have to etch the aluminum surface in order for the paint or primer to adhere properly. As the article notes, they are using an acid to etch the surface.

I don't think the aircraft painter's route is the most appropriate for an automotive body. Paint on an airplane is subjected to a far more stressful environment then a car's paint job is.

So maybe the right answer on painting aluminum successfully would be found in the boater / marine forum discussions. The boaters have a pretty long history of 'do it yourself' painting of their aluminum bass boats etc. So you could probably pick up there how they are able to successfully get marine paint to adhere securely.

IF I had an aluminum bass boat sitting in my garage and I wanted to paint it red... I would probably remove the paint that was on there.. and then score the aluminum surface with something like a 160 grit sand paper. My theory or train of logic would be that that scoring by the sand paper would provide a more than adequate surface for the primer to adhere to. And I am pretty sure that I would tend to lean towards laying a primer layer and smooth sanding it, prior to moving on to the paint stages. The primer would have the ability to fill in the scoring or the aluminum, while giving me an initial surface to work smooth - to give a good subsurface for the paint to build on.

One thought that just struck me... is a warning about sanding aluminum... and that is to be sure to wear a mask when sanding that metal. There is a proven link between aluminum and Alzheimers... and so you really don't aluminum particles being sucked into your lungs.

I am not sure about the differences between automotive aluminum, marine aluminum and aviation aluminum. My gut instinct is that the aviation aluminum is probably the highest quality. And so it probably does have different attibutes for when you are doing a surface preparation prior to painting. The automotive and marine aluminum probably share a closer similarity to each other and probably do not need as complicated preparation as the aviation aluminum.

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