Re-decking an aluminum bass boat

Discussion in 'Metal Boat Building' started by racase122, Jul 11, 2007.

  1. racase122
    Joined: Jul 2007
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    racase122 New Member

    You all have probably been asked this a million times, so go easy... :)

    86 Sea Nymph 17' aluminum. Front casting deck rotted thru. Mice got in/under/around. Decided to rip all top decking off. Floor seems fine.

    Factory decking appears to be 1/2" plywood, possibly marine grade, may have been sealed, marine carpet glued on top. Was screwed down with SS screws.

    Questions.
    1. Replace decking w/ Marine grade or womanized (treated) plywood ?
    2. Should I seal the ply with a sealer or a layer of epoxy/glass..?
    3. Use factory SS screws or replace with..?
    4. Other suggestions..?

    This boat decking lasted 21 years before it rotted thru. I will be keeping it garaged from now on.

    Thanks for any help...
     
  2. SamSam
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    SamSam Senior Member

    Try search. PT plywood corrodes aluminum.
     
  3. mydauphin
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    mydauphin Senior Member

    Why not do it in Aluminum?
     
  4. alan white
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    alan white Senior Member

    Use regular plywood, AB 5 ply 1/2". Coat all the surfaces with epoxy, especially edges, which should receive twice as much. Fill any voids, knot holes, gaps along edges), and overdrill all holes, fill completely, and redrill. Use SS screws. #8 x 1" pan or flat head. Little dab of construction adhesive on each screw will seal the heads.
    The underside will always rot before the top surface, so if you but a quart of epoxy resin , (West System 5:1), make sure the underside is favored for thickness.
    This should last for a long time.

    alan
     
  5. racase122
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    racase122 New Member

    Gentlemen,

    Thanks for the advice.

    Sam Sam, I didn't know that PT plywood would react with the aluminum. Thanks...i'll let several friends know this also.

    Alan, I will probably go your route. Seems less expensive than redecking with aluminum sheets as dauphin suggested. But aluminum might be stronger and will never rot again..!

    Up here in Northern Michigan the summers can be short and the winters brutal. I am a weekend angler so anything that gets me back on the water, the sooner the better..

    Good fishing to everyone !
     
  6. August Ice
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    August Ice Junior Member

    When using epoxy do you still use the woven cloth material as a basis like you do with fiberglass?

    Jan
     
  7. alan white
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    alan white Senior Member

    Epoxy is different from polyester in many ways. Epoxy is a great adhesive, a waterproof coating, and a structural filler. It also happens to be a good resin for fiberglass lamination.
    Polyester is primarily a laminating resin.
    So in laminating fiberglass or other fabric, either resin can be used. West System #105 epoxy resin will laminate cloth well in its out-of-the-can consistency. Yet, adding thickeners with various properties turns that same #105 epoxy resin into a whole bunch of different adhesives, fillers, and structural materials. As is, it is a great adhesive and waterproofing coating.
    Polyester is, guessing, maybe a third or a fourth as much money as epoxy.

    Alan
     
  8. racase122
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    racase122 New Member

    Alan,
    So all I need to do is thoroughly coat the plywood with epoxy, let dry completely, then glue down new carpeting and screw it back down on the boat..? Am I correct in assuming I don't need to add the polyester cloth as additional strength ? I had planned on just epoxying the wood then carpeting, then redecking.
    The origional decking was apparently just epoxied or clear coated, covered with carpet and screwed to the aluminum framing in the boat.
     
  9. alan white
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    alan white Senior Member

    Yeah, just coat the wood with epoxy. No (glass) cloth is needed. Two coats will seal better than one, especially edges. Drill all the holes first, then coat the insides of the holes while you're coating the faces.

    Do cover the epoxy with something, carpet or paint to protect the epoxy from UV light, which degrades it.

    A.
     
  10. August Ice
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    August Ice Junior Member

    Ok Now I get it ... But I was only going to epoxy and allow the surface to be washable.. I thought putting carpet on would just hold onto moisture and encourage eventual rotting. I wonder if Rhino line or a similar product would stick to epoxy?
     
  11. alan white
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    alan white Senior Member

    But all you have to do is paint the epoxy-coated surfaces. I do not like carpet myself. Racase122 indicated wishing to carpet over the ply, which means paint isn't required--- the epoxy has its UV shield in the carpet.
    I agree more with your thinking--- make it washable. So in your case, paint the pieces after sealing with epoxy.

    Alan
     
  12. racase122
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    racase122 New Member

    August and Alan,
    You know, I never really considered painting over the epoxy....huh...
    That actually sounds like a good idea.....but wait......will the epoxy dry clear....?
    If it did could I paint first..?
    No, that sounds like a bad idea...epoxy first then paint...?
    What type of paint can you use over epoxy...?

    Roger
     
  13. alan white
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    alan white Senior Member

    Consider epoxy inert---- ANY paint can be used over epoxy. The suggested paint would be polyurethane paint. Even latex house paint would be fine though.
    I would personally use polyurethane deck paint, an alkyd (oil-based) paint you can get for $30.00 a gallon. I'd add a bit of thinner to it and foam-roll it on without primer, with the piece lying flat--- two coats.
    Sand the epoxy surface with 220 grit first, so the paint has something to cling to.
    Much better than carpet, I think.

    Alan
     

  14. August Ice
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    August Ice Junior Member

    Alan thank you once again for all of the expertise you are providing.

    jan
     
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