paint drying problem

Discussion in 'General Modeling' started by Nobby, Dec 14, 2011.

  1. Nobby

    Nobby Sr Member

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    Hi all,

    I'm hoping someone here will be able to help solve a little problem for me.

    I'm building a Galaxy Quest Nebulizer gun made from resin and there are small areas on the handle where the paint just doesn't seem to dry. It always remains tacky.

    The rest of the pistol has accepted primer and top coat without a hitch.

    I have sanded the handle back several times to bare resin and I cannot see any problems with uncured resin. It always appears 'dry'. I even tried sealing the resin with a thin layer of superglue. Again the surface seemed dry and ready to accept paint.
    But guess what? After applying the primer and leaving it to dry, I still had small areas that remained tacky!

    Anyone have any tips or ideas?
     
  2. robn1

    robn1 Master Member

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    Is it the primer or the paint that isn't drying? And what paint are you using?

    Uncured resin is my first thought, but if you've determined that's not it then I just don't know.

    Maybe strip the handle and spray it with self etching primer.
     
  3. Nobby

    Nobby Sr Member

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    Yeah, I first thought uncured resin too.

    The problem was initially with the primer, which was Rust-oleum general purpose surface primer. But it was fine on the other parts.

    This morning I have sanded back the tacky areas again and tried going with my top coat of Plastikote Metal Protekt in silver.
    'So far' it seems to have cured the problem, but I'll update with progress later in the day if I can get any more coats on.
     
  4. Nobby

    Nobby Sr Member

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    well I must say that I am baffled........

    The top coats seem to be drying without a hint of tackyness! :)

    Problem solved I guess
     
  5. BLACKULA727

    BLACKULA727 Active Member RPF PREMIUM MEMBER

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    Is it urethane resin? I have found that if you don't mix the two parts adequately enough or even if the ratio of the two parts are off, that the resulting casting will leak an oil substance. It will apear dry, but once you coat it with primer the oil stuff present causes the paint to not cure. Good news is that it will eventually stop and you can then paint. bad news is, it can take a long time. Again this is only what I have personally noticed. So, take it for what its worth. I'm no prfessional at this, so there may be a better explanation.

    Tony
     
  6. Nobby

    Nobby Sr Member

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    yeah, that's what I was originally thinking.
    but at the moment all seems well. Let's hope that my choice of topcoat paint has solved the problem...............
     

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