Painting aluminum?

[R. Maxwell]

I am getting ready to start my first build and I was wondering if I skin my tear in aluminum could I paint it? I am asking because I saw a tear on a site that was painted the same color as the tow vehicle. Thats what I am thinkning about doing.

I know cars have aluminum outer panels but I don't know if there is anything special about them.

If this has already been address, if some could point me to the right thread it would be appreciated.

Thanks
Rich

[ARKPAT]

You might gleen some information from this part of the forum discussion on painting Aluminum






Pat

[james tillitt]

Painting aluminum is simple. Talk to any auto paint store about this. They can get you pointed in the right direction, depending on what product you go with. I could lay it out for you but the process is different for different types of paint processes

[Trackstriper]

You might look into prepainted aluminum sheets from a sign supply company or other supplier. The white sheets are typically not much more expensive than mill finish aluminum and have been properly coated. Colors are available for more $$, but if you were to use the white, I would think that you would at least have a well primed surface, and that's probably the biggest bear when painting aluminum...surface prep. You might have to test a small sample (scrap) of the aluminum with the type of auto paint that you are thinking of using to see if there are any incompatibility issues.

You might look here to see what is typically available:

http://www.alumapanel.com/subcategories.cfm?lines_ID=3

J.B.

[madjack]

...surface prep is the key...sand lightly, clean well, use a primer made for aluminum and compatible with the paint you wish to use...your auto paint supplier will help you with this.......
madjack

[bobhenry]

When I worked in the lubricants lab we worked with corrosion resistant and lubricating paints. These were applied to steel or aluminum coupons.
and subjected to various tests. The salt cabinet was the main test. A warm salt water mist was fogged in the cabinet to simulate years of exposure in weeks.

To prepare these coupons they were degreased in an alkali solution and warm water rinsed they were then acid etched in an acid bath and warm water rinsed and force air dried there were final degreased with the same reduced recommended for the primer or top coat to be applied.

You can simulate this with a good hot soapy bath and rinse. Then a white vinegar scrub with 00 or 000 steel wool. Rinse again and allow to dry.
wipe with a lint free rag liberally moistened with the reducer you plan to use with your acid etch primer. Follow primer prep instructions ( some do not require sanding) then top coat per instructions.

[madjack]

BH, really like your EXCELLENT directions ...could I add an improvement...use a red scuff pad or some wet sandpaper with the vinegar instead of the steel wool...I would be leary of using steel wool on aluminum, due to the possibilty of embedding some of the steel into the aluminum, therby having the possibility of inducing "rust" into the aluminum...I don't know if this would be an actual problem or not.......
madjack

[bobhenry]

Kuddo's Jack. The scotchbright pads would do a good job of loosening the oxide and eliminate the chance for the steel crumbs to be trapped at the trim. Would be real emberrassing to explain why your aluminum was rusting and ruining the paint job.

However with dissimilar metal you get a battery maybe you could power the lights. Nah!

[asianflava]

At the paint shop I worked at, we'd do an acid etch and an alodine coating on the aluminum parts. After that, it was up to what the customer wanted to pay for. Some went directly to paint, but the best was epoxy primer, very tough stuff.

[HossHoffer]

They have pretty well summed it up. We use two acids in aviation. Phosphoric acid to clean and etch and Alodine (chromic acid) to etch and add corrosion resistance. Scotch brite is the pad of choice to clean and scuff and is often used on a orbital sander. Of course for your application a good degreasing and light sanding with the scotchbrite should work fine.

[R. Maxwell]

I thank you for all the resposnses and information. This may be more than I planned for my first tear so I may leave it standard aluminum finish. Who knows when the time comes. Nothing ventured nothing gained right.

Rich

[ssrjim]

I thank you for all the resposnses and information. This may be more than I planned for my first tear so I may leave it standard aluminum finish. Who knows when the time comes. Nothing ventured nothing gained right.

Rich

Or just pay the bodyshop like I did

[R. Maxwell]

Hey Ssrjim, I looked at you photos with my wife and that is exactly the way I was thinking of doing it. Matching body color with aluminum trim. Your trailer looks great. Nice matching pinstriping also.

Again nice job
Rich

[kurtibm]

They have pretty well summed it up. We use two acids in aviation. Phosphoric acid to clean and etch and Alodine (chromic acid) to etch and add corrosion resistance. Scotch brite is the pad of choice to clean and scuff and is often used on a orbital sander. Of course for your application a good degreasing and light sanding with the scotchbrite should work fine.

The manufacturer-applied clear-coat on my 10 year old TD failed, so I am stripping it off.
What would the aluminum experts recommend as a wipe or brush-on corrosion-inhibitor?
Should I just leave it alone (it's mill finish) or treat it with something like ALODINE 1001? I don't want a 'coating' as such, where it may need to be stripped again, more like a 'treatment' or the like that would leave the surface sheen about like it is.

Thanks in advance,
Kurt

[madjack]

Kurt, there is are a couple of different products out there...one that I have read a lot about(haven't used it myself) is SHARKHIDE...it is a wipe on protectant for aluminum surfaces...google sharkhide or sharkhyde and get lots of hits on it from fishing/boating forums and such...they seem to like it a lot............
madjack