CPES™: Clear Penetrating Epoxy Sealer???????

Discussion in 'Wooden Boat Building and Restoration' started by aaronhl, Jun 10, 2015.

  1. aaronhl
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    aaronhl Senior Member

    I have used West System epoxy before but I don't like how thick it is. Thinning it makes it easier to work with, but once it hardens it is still a pain to sand.

    I heard there is the Penetrating epoxy 1:1 that is very thin and easy to work with. After it drys you can sand lightly and spray with clear coat.

    Anyone have any experience using it? Basically I am using it for an outside layer on a model boat that is only in the water for a few minutes at a time.
     
  2. FMS
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    FMS Senior Member

    What are you coating with the epoxy? (plywood?)
    Is the problem with west system that it isn't leveling and is hardening with tool marks from your working it?
     
  3. aaronhl
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    aaronhl Senior Member

    It is birch plywood, in complex shapes. I will have drips all over. And YES hardening with tool marks like if I scrape the epoxy on. Brushing is too time consuming...then when hardened Sanding West System is a pain because of the shapes of the parts.

    I like the idea of spraying clear(cans only, I don't have a compressor) because it will give a smooth and shiny finish, but I need a solid layer underneath that is easier to work with than West System.
     
  4. rwatson
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    rwatson Senior Member

    The trick is to apply the resin sparingly and then warm it with a heat gun. This reduces the viscosity to make it easy to apply thinner coats. Also. Use a roller not a brush
     
  5. LP
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    LP Flying Boatman

    If it is only in the water for a few minutes at a time, the water barrier properties of epoxy may be overkill for your project(and cause a lot of additional work). Maybe several layers of brushed on varnish would build a substrate that could easily be sanded for the final spray coat(s).
     
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  6. aaronhl
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    aaronhl Senior Member

    Good info
     
  7. PAR
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    PAR Yacht Designer/Builder

    CPES isn't waterproof (not by a long shot), so you need to reconsider it's application. In fact, high quality paints (LPU's) are more water proof than CPES.
     
  8. waikikin
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    waikikin Senior Member

    Seems like the go, plenty "full size" small vessels survived for decades sailed on the weekend through summer just using varnish & simple to freshen up.... sand one off.... put two on....

    Jeff.
     
  9. michael pierzga
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    michael pierzga Senior Member

    Dont know much about CPES. The stuff is not used in the Pro sector.

    If you are painting epoxy resin , a low viscosity resin is worthwhile.

    international EpiGlass epoxy resin is an easy to use low viscosity resin. Much lower that West, and it gives a good finish.

    http://www.yachtpaint.com/usa/diy/products/epiglass/search.aspx

    Roll and tip.

    Be sure that the substrate is at room temp . Remember outgassing. The substrate must be in cooling cycle, not heating cycle or it will blow bubbles.
    Use medium or slow hardener...never fast

    Dont alow the resin to exotherm in your roller tray...work fast , smaller batches or pour the resin directly on the substrate
     
  10. PAR
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    PAR Yacht Designer/Builder

    Out gassing is only possible if the wood is raw and you use inappropriate techniques for the first coat. The first coat, should be applied so no pools of goo are visible and it all has been pushed or permitted to soak into the raw wood fibers/cells. This way, there's nothing on the surface for the bubbles to form in and attempt to rise up through, hence, no pin holes for out gassing. The hot on hot method can help too, both are covered in my "Tips and Tricks section, if you have a look in the "Coating Raw Wood" paragraphs.
     
  11. aaronhl
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    aaronhl Senior Member

    "The first coat, should be applied so no pools of goo are visible and it all has been pushed or permitted to soak into the raw wood fibers/cells."

    Are you talking about scraping it into the wood?

    Some good information guys
     

  12. PAR
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    PAR Yacht Designer/Builder

    I mash the first coat of epoxy into the grain, physically trying to make it penetrate with a putty knife or plastic applicator. As I move the goo around, some pooling occurs, so I move this excess to raw areas, for more mashing. Again, the idea is to have no pools of goo on the surface, just raw wood that's been coated, preferably with a hot on hot technique too. Scraping suggests I'm trying to remove something. Mashing is a better way to describe it. Hold the knife at a fairly flat angle and press hard, as you move the goo around the area. My usual techniques has me spread the epoxy over a large area first, letting it soak in, then go back and mash it in with a heavy handed putty knife.
     
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