3/8 plywood vs 1/2

Discussion in 'Boat Design' started by LastSamsara, Mar 21, 2021.

  1. LastSamsara
    Joined: Feb 2021
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    Location: Souris Pei Canada

    LastSamsara Junior Member

    Hey, in the process of building nancys china dc15 in which the plans call for 3/8 marine plywood for the hull, with the current lumber shortages and my location I'm only able to get 1/2 inch, it only calls for 4 sheets and was just wondering if I could get away with it.. there's not a huge amount of drastic bending it seems but would the extra weight be an issue?
     
  2. BlueBell
    Joined: May 2017
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    BlueBell "Whatever..."

    Do the plans call for good one side 3/8 or standard?
     
  3. LastSamsara
    Joined: Feb 2021
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    LastSamsara Junior Member

    They kept it simple, 3/8 marine grade plywood was all it said
     
  4. Russell Brown
    Joined: Jul 2012
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    Location: washington state

    Russell Brown Senior Member

    That boat would be difficult to build with 1/2" ply.
    Look for non-domestic 9mm thick ply, preferably Okoume. It doesn't pay to try to save money on plywood
     
  5. LastSamsara
    Joined: Feb 2021
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    LastSamsara Junior Member

    Fair enough, alright I'll do some more digging, just hard to believe how scarce things are now a days
     
  6. BlueBell
    Joined: May 2017
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    BlueBell "Whatever..."

    I don't believe it's an expense issue Russell but rather a supply issue.
    We are really short on wood these days up here in the Great White North.

    LastSamsara, Yes it will make a weight issue.
    Unless you can get good both sides 1/2 that is really less than 7/16.
    OR
    Have you considered laminating door skins on the build?
     
  7. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    Here is a link to Nancy's China on Sam Devlin's page for reference.
    Nancy’s China 15 https://devlinboat.com/nancys-china-15/

    LS, which rig are you planning on using on your boat?

    Re the 3/8" hull shell thickness, would it be feasible / practical to use two layers of 3/16" plywood (assuming that it is available)?
     
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  8. LastSamsara
    Joined: Feb 2021
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    LastSamsara Junior Member

    I haven't thought of that, but was playing with the idea of running the 1/2 through a thickness planer to bring it down to 3/8, I've called around and theres only one other spot I can get 3/8 and it's crazy expensive, and I'd have to pay for shipping too
     
  9. LastSamsara
    Joined: Feb 2021
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    LastSamsara Junior Member

    Was planning on going with a bermuda rig for simplicity, and I dont think so, the most standard size around seems to be 1/2
     
  10. BlueBell
    Joined: May 2017
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    BlueBell "Whatever..."

    Is the designer available for comment?
    That would be your best bet.

    Planing 1/2 down, ugh, not an option in my book.
    I'd add (laminate) door skin to 1/4" before planing 1/2.
     
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  11. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    If 1/4" thick plywood is available, you could maybe use this, and add an extra layer of glass cloth to compensate for the 1/8" of plywood that is 'lost'?
     
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  12. LastSamsara
    Joined: Feb 2021
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    Location: Souris Pei Canada

    LastSamsara Junior Member

    Hey might be yes, maybe that will be my next move, 1/2 seems to be all people are carrying
     

  13. fallguy
    Joined: Dec 2016
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    fallguy Senior Member

    Nice boat.

    Not sourcing 10 or 9 mm is a false premise.

    And a terrible way to try to build her. You will need to kerf cut the 1/2" to make it bend that much.

    Good luck.
     
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