Enclosed buoyancy compartments on wood/plywood boats

Discussion in 'Boat Design' started by laukejas, Jun 27, 2019.

  1. laukejas
    Joined: Feb 2012
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    laukejas Senior Member

    Alright, thanks for the specifics, but why do you put that foam in the first place? Since it doesn't adhere to plywood, that means the water can still get around in these compartments, and drying them out with the foam is much harder, because it blocks ventilation, isn't that so?
  2. Ike
    Joined: Apr 2006
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    Ike Senior Member

    Actually the answer is simple, an overabundance of caution. On the 12 foot boat I really didn't need to put foam in the air chambers. On the next boat I built, an 8 foot sailing dinghy, I used just air chambers. But on the 12 footer my thinking was, it's going to have a 2hp outboard so I should put some flotation under the rear seat to float the engine, in the case the boat was swamped. In the original configuration that seat had a hatch cover, and like you I worried about water getting in. But I never used the compartment for storage and in fact was usually sitting on the hatch cover. So I just sealed it all up, but left the foam in there. It was glued in place with epoxy and fiberglass and would have been a real mess to remove. But the compartment under the middle seat is open and used for storage and has about 2 cubic feet of foam under the seat, but it doesn't protrude into the storage part of the compartment. The bow seat was the same as the rear seat. It has about 3/4 of a cubic foot of foam in it, which left room for storage. But again it was never used for that, so when I sealed up the rear seat I also sealed up the bow seat.
  3. sharpii2
    Joined: May 2004
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    sharpii2 Senior Member

    You can always have inspection plates on all your floatation chambers. This is common practice in the Puddle Duck community. When the boat isn't being used, remove the plates.

  4. tlouth7
    Joined: Jun 2013
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    tlouth7 Junior Member

    A few days a year I would guess. It spent several weeks afloat for a few summers. Summers spent in a dinghy park with a cover on, winters in an open garage. 50 years is not terribly old, with a bit of care.
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