Painting anodized aluminum

[George Elston]

I recently took a small sign job, and quoted an anodized aluminum base. I was figuring on just using vinyl letters. Then the customer asked if the sign could be painted instead. No problem I said. Fortunately I did a test first and found the paint pulls off the aluminum. Is it possible to paint anodized, and if so is any paint better, or is some kind of surface prep needed?

Thanks

[Joe Pelonio]

I had that problem once, and was told to use an etching primer first, so I bought a rattle can of it from an automotive paint supplier and it worked. If I remember correctly I used Krylon over it, but it should work for most paints.

[George Elston]

Thanks Joe, I'll get some this afternoon. Did you spray the entire sheet or apply the stencil first and only spray the areas to be painted?

[Joe Pelonio]

I sprayed the whole sheet.

[Doug Bergstrom]

When we have done this I sanded down the sheet with 320 grit and orbital sander. Prime with MF Adhero or any good primer that will stick to vinyl will usually stick to aluminum fine. Then you can paint with anything you want over the primer.

[Phil Thien]

I have used XIM 400 White in a rattle can. They refer to it as a bonder/primer. They suggest its used for things like ceramic tile, aluminum, etc. It worked great for me, but I don't know if it works as good as a dedicated aluminum primer.

Seeing as you can get XIM at many Ace stores, it may be worth a side-by-side test against the aluminum etching primer. I wouldn't be surprised if the XIM actually outperformed because the stuf I used stuck like liquid nails.