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Thread: How To Prep Aluminum For Paint

  1. #21
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    One trick is to rub the aluminium down with wet-and-dry paper using the primer as the lubricant. This ensures that the paint gets right onto the aluminium, not on the surface oxide, which can't reform under the paint, as the paint keeps the oxygen out.
    Gluing aluminium together with epoxy works well if the glue is applied this way, too.

  2. #22
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    Good idea! Never thought of that.

    Ummm, seems like it could get really messy, though.

  3. #23
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    Quote Originally Posted by DATo View Post
    Why do you want to paint it? It looks great just the way it is.

    When I had to do this from time to time at work before I retired I used to bead blast and then prime and paint with Krylon spray.
    Or cover it with wood grain contact paper. Then it will blend in with wall paneling.

  4. #24
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    I agree with a couple of other posters, looks nice natural. But if you want or need to paint it, the best, easiest way would be to nip down to your local blast finishing place. Glass beads or fine AlOx.

  5. #25
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    Nix to that. I have tried that in the past and the Contact paper shrinks over time and leaves gaps around the edges.



    Quote Originally Posted by reggie_obe View Post
    Or cover it with wood grain contact paper. Then it will blend in with wall paneling.
    Paul A.

    Make it fit.
    You can't win and there is a penalty for trying!

  6. #26
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    Green Scotchbrite? But there are about a half dozen different grades of Scotchbrite that are green, perhaps more. I have two of them as well as a fine one that is white. Perhaps I will try the finer green one first.



    Quote Originally Posted by epicfail48 View Post
    I'm calling shennanagins on a metal paint not needing primer. I agree with the previous recommendations, scuff up the surface, prime and paint. Been a while since I've done any aluminium but I seem to recall green scotchbrite leaving a good surface for paint.
    Paul A.

    Make it fit.
    You can't win and there is a penalty for trying!

  7. #27
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    So, is there any real evidence that the oxide on an aluminum surface will actually prevent paint adhesion?
    Paul A.

    Make it fit.
    You can't win and there is a penalty for trying!

  8. #28
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    Quote Originally Posted by Paul Alciatore View Post
    So, is there any real evidence that the oxide on an aluminum surface will actually prevent paint adhesion?
    Without being dogmatic about this, Paul, I would think that painting the oxide means that one would then be relying on the paint's sticking to the oxide AND on the oxide's sticking to the aluminium.

    Painting directly on the aluminium, on the other hand, would seem to halve the possible failure modes.

    As far as I know, primers for aluminium are designed to go on aluminium, and are not designed to go on the oxide. My understanding of the situation is that any paint job on aluminium must exclude atmospheric oxygen to prevent that irritatingly active metal from forming its oxide layer again. I may, of course, be completely wrong, but the foregoing makes sense to me.

  9. #29
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    Wait, theres more than one grade of green? Ive only ever seen one... At any rate, the green that im talking about is the one they sell at loves with the sanding supplies, next to the grey and white pads.

  10. #30
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    Quote Originally Posted by Paul Alciatore View Post
    So, is there any real evidence that the oxide on an aluminum surface will actually prevent paint adhesion?
    Not really... the oxide is extremely well bonded well to the the surface and hard. Anodizing first (thick aluminum oxide) is a perfect way to get paint to stick.

    Aluminum oxide forms almost immediately the AL is exposed to oxygen and is protective for the base metal.

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