Aluminum Painting/Finishing Question...

[elmo_4_vt]

Sorry Guys,
I couldn't find what I needed in the search, so maybe you all could help me out.

As you may or may not remember, I'm using a old alum. truck body as part of my tiny trailer. I spent all Sunday sanding down the sides and top. What it looks like it has in the way of Layers is, 1-the green alum. etching primer, then 2-a blue automotive one-step paint, then 3-a poor red paint that is mostly faded and coming off in some places. After completely stripping the top surfaces, where the paint was the worst, I spent Sunday sanding the sides, and feathering all edges where there were chips, or dents. What I was left with was a lot of dull red, sanded paint on the sides, with some spots of blue, and some spots of sanded, bare aluminum. The top surfaces are pretty much bare. The blue automotive paint doesn't come off very well with stripper, so I think the best I could hope for is to spend a few days trying to get the red paint off with chemical stripper, then sanding all the edges down.

My question is, on the bare spots, do I have to use the green alum. etching primer, and regular primer on the still-painted portions? Or can I use regular primer on the entire piece since the bare alum. is well scratched, dented, and/or sanded.

Thanks for any help all.

Don

[robert johnson]

Hi Don, I'm an aircraft mechanic and have worked with "old aluminum" for 25 years. of corse the self etching primer is the best method, but I have had just as good of luck doing exactly what you are thinking of doing, by primering over the sanded areas with a good sanding primer. as long as everything is really clean, and scuffed up with around 320 wet or dry. mabey a little coarser grade for areas you want to body fill. good luck.............Bob

[asianflava]

That green primer might be Zinc Chromate primer.

[Kstoner]

use a self etching primer or an epoyx primer. the follow that with a high build primer and then your color. Without the self etching or epoxy primer you have a chance of everything peeling off. This will only be a few more $ and about 30 minutes to spray the self etching or epoxy, an could save you down the road.