trouble getting good paint finish

Discussion in 'Boatbuilding' started by georgiahemi, Jun 3, 2010.

  1. georgiahemi
    Joined: May 2006
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    Location: Georgia

    georgiahemi Junior Member

    I am making a plug for a radio control boat that is about 56 inches long. I have the plug made. I have been paintng it with Interlux two-part paint. The first time I did it, rolled it on, then tipped it out with a brush. Well, I had a BUNCH of sanding to do after this. Now that I have it all sanded out, I tryed to paint it again with the same kind of paint, but I used the Preval spray guns that you can buy at West Marine. Now it looks like I have a BUNCH more sanding to do again. I can not get a smooth finish. Does anybody have any ideas? I know I need a regular spray gun to use with an air compressor, but this is kind of out of the question($$). I just need a better way of painting it so I can get a smooth finish. I want to get it perfect so I can start making a mold from it. Any ideas would be most appreciated. As you can tell, I am about to pull my hair out!
     
  2. ecflyer
    Joined: Jan 2009
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    Location: Green Bay, Wisconsin

    ecflyer Junior Member

    Try thinning the paint 10% to 20% until you get proper flow and leveling of the paint on the surface. You need to experiment on a test piece. This applies no matter if spraying or using roller & tipping applications.

    Have a Spiffy G'Day
    Earl
     
  3. georgiahemi
    Joined: May 2006
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    Location: Georgia

    georgiahemi Junior Member

    Thanks for the advice. I did try both times to thin it. I guess maybe I didn't thin it enough.
     
  4. missinginaction
    Joined: Aug 2007
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    Location: New York

    missinginaction Senior Member

    A couple of questions.

    1. Did you apply thin (say 4 oz/sq yard) cloth to the surface? If not I'm assuming that you at least coated the surface with epoxy resin and finished smooth?

    2. Did you apply the proper epoxy prime coat? Did you sand the prime coat? How well and how fare?

    Lighter colors of Perfection will go on with the roller and tip technique very smooth. I've used Perfection on my Silverton restoration with great results. I can tell you that proper preparation of the surface before painting is the key to a good finish.

    If you spend 95% of your time getting a good smooth fare surface the painting itself is almost an afterthought.

    Proper mixing, induction and painting in as dust free an environment as possible all help.

    Also, if you value your life don't ever spray Perfection without proper extensive positive pressure respirators and a full suit on. Sprayed two part polyurethanes are highly toxic when inhaled. I wear a good organic respirator and suit even when I roll and tip perfection and I get the hell out of there as soon as I'm done.

    I love the results that the paint gives but respect it's toxicity.

    MIA
     
  5. marshmat
    Joined: Apr 2005
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    Location: Ontario

    marshmat Senior Member

    This probably isn't what you want to hear.... but fancy two-part paint on a plug seems excessive. The paint on a plug doesn't have to be polished to a yacht finish- all that matters is the actual surface that the mould will touch, ie. the release wax. Once you have it smooth and fair (with no drips, runs or ridges), I wouldn't worry too much about the shine on the paint- your skill with applying and polishing the release wax will have far more impact on the final finish.
     

  6. missinginaction
    Joined: Aug 2007
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    Location: New York

    missinginaction Senior Member

    My mistake for not reading the original post more carefully. Working with a male mold you should only need to epoxy the mold good and fair, sand it down and apply a mold release agent. Are you working on a male or a female mold?
     
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