Can I fiberglass the bottom of a plywood boat?

Discussion in 'Materials' started by Brenny, Jan 22, 2015.

  1. Brenny
    Joined: Jan 2015
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    Location: Central MN

    Brenny Junior Member

    Hi all,
    I have a 1955 plywood Delta boat. I am no boat builder... But am trying to restore this to a working condition. Keep in mind it will only hit the water three times a year and sit on a trailer the rest of the time. This boat had a small rot spot on the stern of the boat. I replaced the rotting wood on the back with new mahogany. The 1/4 bottom is slightly rotten, so I picked out most of the 1"x1" spot and filled it with Six-10 epoxy. I was then going to fiberglass the bottom of the boat below the water line. Is this a good idea??? Some old wood boat guy told me this is a terrible idea, and the boat will rot out in 3 years. Please let me know your thoughts and suggestions. Thanks for all your help!
  2. Mikeemc
    Joined: Nov 2014
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    Location: South Carolina

    Mikeemc Junior Member

    Not seeing the boat or condition , be hard to say. But on the other hand can you spell bird bath. Personally I'd reply the bottom , might be hidden spots of rot at this point and age. Nice little boat by the way.
  3. pauloman
    Joined: Jun 2010
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    Location: New Hampshire

    pauloman Epoxy Vendor

    use an epoxy that will bond to a wet or damp surface - not regular marine epoxy - also one with a bit of flex
  4. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    If you fiberglass over a wet surface the boat will rot within less than a year. It should be completely dry.
  5. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    This is a traditional plank over frame build, which isn't well suited to a partial sheathing over an unencapsulated surface. This isn't to say you can't, but it's a lot more work then it might initially seem, if you'd like it to last.

    Simply put, traditional builds do best if repaired with traditional methods. In this case, you'll cut out any rot, well back into known good wood, scab in a repair, then prep for paint. If you've found rot, it's very likely there's more, as generally there's a lot more you can't see, buried in the wood, inside joints, under stringers and other structural elements, etc. As a rule, it's treated like cancer and if you don't get it all, you'll just be performing these tasks again, probably sooner then you think.

    This said, if you only want a few more seasons out of the old gal, then go a head and sheath her with cloth, though I wouldn't bother, as reasonable repairs will last about as long anyway, so why make more work for yourself.
  6. Ike
    Joined: Apr 2006
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    Location: Washington

    Ike Senior Member

    Glassing an old boat is a common short term fix, but as was said, it won't really extend the life much longer. Better to do it right if you want to keep the boat for a long time. However if you are just trying to get a few more years out of it, go ahead.

  7. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Traditional repairs are usually easier and faster to do then sheathing over sound repairs. Simply put, in either case you'll need to have solid planking and it's attachment, regardless of it being a traditional repair or a sheathing job, so the sheathing aspect takes more materials and labor comparatively.
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