Alternative to Epoxy For Sealing off Core After Cuts

Discussion in 'Materials' started by Chotu, Aug 25, 2020.

  1. Chotu
    Joined: Mar 2018
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    Chotu Junior Member

    I’m deathly allergic to epoxy. As in, anaphylactic reaction and hospital time.

    My boat is epoxy/corecell for the most part and epoxy/balsa in a few areas.

    I need to finish off the boat’s interior and place deck hardware and things like that.

    This involves drilling (and cutting) into the laminate, exposing the core.

    What can I use to properly seal off the core in these cases that isn’t epoxy?
     
  2. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Paint ! What is it coated with currently ?
     
  3. Chotu
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    Chotu Junior Member

    It’s not coated at all. Maybe there is some confusion.

    I’m talking about doing this:

    [​IMG]

    [​IMG]


     
  4. Mr Efficiency
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    Mr Efficiency Senior Member

    What were you intending to coat it with ? If in the sun, you would need to coat.
     
  5. Chotu
    Joined: Mar 2018
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    Chotu Junior Member

    Can you see the pics?

    The area in question is inside the panel. In the core. I’m asking what material, aside from epoxy, I can use to close out the core.

    The paint on the surface of the panel is irrelevant
     
  6. Mr Efficiency
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    Mr Efficiency Senior Member

    If you aren't going to use epoxy, then paint is about what you are left with. The question is, what kind of paint. The main concern would be the balsa, the rest of it is pretty well not a risk, I guess you could get a little water wicking into the laminate from the cut, but no big deal. If you have balsa squares you may have a pathway for water intrusion.
     
  7. fastwave
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    fastwave Senior Member

  8. upchurchmr
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    upchurchmr Senior Member

    If you want the strength and water sealing of the picture, I don't know anything else that works.

    Sikaflex or another sealent will not give you the strength of epoxy.

    Do you have a lot to do? Could you get someone to do the fasteners you need?

    Does your reaction happen to uncured epoxy or also cured epoxy that you drill thru?

    What are you building? Just being nosey. :)
     
  9. Rumars
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    Rumars Senior Member

    Hazmat suit, bottled air, full body cooling suit and a decontamination shower before taking it off. Or pay someone else to do it. No really other option if you have such a severe allergy.
    Long term I would sell the boat and get into steel, or traditional wood, otherwise you face the same thing again and again with any repair or modification. At least with those materials you have the option to completley avoid any epoxy products.
     
  10. Mr Efficiency
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    Mr Efficiency Senior Member

    There is no need to seal either the epoxy laminate or the corecell, that I can see, It isn't going to a real problem, but the balsa is another matter. Just run a wick saturated with wood primer through the holes. Let the first coat dry, then do it again, that should be enough. Of course if you have gaps between balsa squares, or foam squares, intersected by the drilled holes, then water ingress is possible. Failing that, use a bedding compound both sides of the fasteners, so that water can't get past the holes. You can worry yourself silly about such things, but it isn't the end of the world if water contacts that laminate or the PVC core. Won't hurt it.
     
    Last edited: Aug 25, 2020
  11. fallguy
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    fallguy Senior Member

    You don't want to use those bolts. - flat headed tapers fit into the countersinks; no washer. If you want to washer then don't countersink. Conversely if you want to pan and washer; no countersink.

    Apply a bead of silicon or 3M 5200 or 3m 4000 or 4200 to the screw and around the topz. Clean up with acetone. You can also use butyle gum tape, but the caulk is a more certain seal.
     

  12. Blueknarr
    Joined: Aug 2017
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    Blueknarr Senior Member

    Thickened polyester will work in this application.
     
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