Spraying a clear coat

Discussion in 'Fiberglass and Composite Boat Building' started by aaronhl, Jun 30, 2014.

  1. aaronhl
    Joined: Aug 2012
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    aaronhl Senior Member

    I have a piece of wood (basically a rc boat sponson) that has many sides and angles that I think should be sprayed instead of rolled/brushed. I've asked similar questions and researched on the board about spraying and applying epoxy resin.

    It seems like epoxy is more for building rather than clear coat. Since the boat will not be sitting in water for extended periods of time, mostly 10 minutes at a time and then dried off, what clear finish should be used to cover?

    All small holes will be filled before spraying and I would like to stay away from scraping a very thin layer of epoxy over the bare wood at first before spraying clear.

    Aaron
     
  2. gonzo
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    gonzo Senior Member

    You can use polyurethane varnish. It sprays well.
     
  3. aaronhl
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    aaronhl Senior Member

    Thanks for the input- is this what you are talking about?
    And would it be okay even for being in the water?

    [​IMG]
     
  4. gonzo
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    gonzo Senior Member

    Yes, but use the high gloss finish.
     
  5. aaronhl
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    aaronhl Senior Member

    Cool I use that with a brush on some other woodworking products. Does it need to be thinned? I know the high gloss is a thin liquid to begin with v. the regular polyurethane

    Now I just need to know what type of gun and compressor to get
     
  6. gonzo
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    gonzo Senior Member

    They make a refillable sprayer. Basically a spray can that can be refilled. It should be enough for a small project.
     
  7. aaronhl
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    aaronhl Senior Member

    I tried that Preval sprayer with no luck it just wouldn't pick anything up. I even tried water and it didn't spray. Maybe Ill give it another shot??

    But I would like to buy a compressor and sprayer because I would like to use it with other staining and clear coat woodworking projects. And later down the road I might be making a rc boat mold that I will need to spray gel coat
     
  8. aaronhl
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    aaronhl Senior Member

    Would a water based polyurethane work in a marine environment? People have recommended spraying that over polyurethane
     
  9. gonzo
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    gonzo Senior Member

    Water based would work OK for interior use.
     
  10. PAR
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    PAR Yacht Designer/Builder

    The Preval sprayer will work, but you'll need to cut the polyurethane a bit. How much depends on the tip size in the sprayer, so some experimenting will be necessary. Cut it just enough to remove spraying stipple.
     
  11. aaronhl
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    aaronhl Senior Member

    How about a marine varnish? How do you cut polyurethane?
     
  12. PAR
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    PAR Yacht Designer/Builder

    Marine polyurethane varnish (spar) can be cut with a few different things, but mineral spirits is the usual solvent. Again, just cut it enough to get it through the sprayer without leaving a stipple on the work. Spar varnishes will add a considerable amount of an amber color to the work, because of the significant amount of UV inhibitors (and some pigment) added. It's not an objectionable amount or color, but some can be surprised by it.
     

  13. aaronhl
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    aaronhl Senior Member

    I was able to spray the ultra clear Minwax polyurethane with the Preval sprayer very easily. Not sure why I was having problems with the pevious one I bought.

    So I am back in business this will help me with all the ideas I have cookin
     
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