Prepping new aluminum for paint

[ANGELO]

Picked up my new gate yesterday. Instead of getting it powder coated im going to paint it my self, Since the rollers will eventually rub through it will be easier to touch up in the future. I think im going to roll on black rustolium hammered with the hardener. Whats the best way to prep this? Can i just spray something on that will etch it, or do i have to sand it all?

 

[Eric]

The quality of a paint job always depends on prep. Sand/scuf so that its clean. Apply self-etching primer. Paint.

 

[subybaja]

Alodine. Look up aircraft painting.

Plane and Simple

Making paint stick to aluminum. By Jon Croke.

www.kitplanes.com

AlumiPrep (or a similar product) is an acid etch that is designed to deep clean the aluminum surface. It does this by removing the oxide coating that normally forms on any aluminum surface (a reaction with the oxygen in the air). Alodine is a chemical that converts the aluminum surface. This conversion produces a coating that provides both corrosion protection and a surface that paint loves to stick to. This new surface does not add any weight and can be primed and painted (or just painted) as desired.

 

[DWT]

Along the lines of alodine you can grab some alumiclean or trailer wash etc from a big truck shop. It's a mixture of hydrochloric and hydrofluoric acid that deep cleans the aluminum and strips it down to it's base metal. That's what makes dull, white aluminum on semis and the like.

Purple power or super clean will do the same thing if you let them soak long enough.

 

[ANGELO]

The quality of a paint job always depends on prep. Sand/scuf so that its clean. Apply self-etching primer. Paint.

the can says primers not needed. should it stil get it?

 

[ExWrench]

the can says primers not needed. should it stil get it?

Yes. Don't skip the etching primer, it's worth it.

 

[Will12785]

1) wash
2) chemical clean (any aluminum paint prep)
3) acetone
4) kbs self etching primer
5) kbs rustseal
6) kbs diamond clear

Don't bother with anything else for paint that will need to be touched up.

KBS is single part so you can stir it don't have to shake it and touch ups are super easy being self leveling.

 

[budget76]

i started a thread a little while back with similar. wound up finding that to do it right, you need some $$ primer for the aluminum. I decided to use steel instead and not **** with bonding to Al

project hasn't happened yet anyway