Another question for Gerr's rule

Discussion in 'Boat Design' started by Samnewbie, Jul 19, 2012.

  1. Samnewbie
    Joined: Jul 2012
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    Samnewbie New Member

    Hello everyone, I'm a student and im designing a 14.5 meters day sailing charter and im planning to use Gerr's rule for scantling.
    I want to use stripe planking for the building method, but instead using cedar, I want to use foam. However, in Gerr's rule, he covered Fiberglass Sandwich or core construction in chapter 6 and Modern Wood-epoxy construction in chapter 11. I have calculate them all in spread sheet but I wonder which one should I use? anyone have any good advice? Many thanks!
     
  2. gonzo
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    gonzo Senior Member

    What is "form"?
     
  3. Samnewbie
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    Samnewbie New Member

    i mean foam core,
     
  4. erik818
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    erik818 Senior Member

    My understanding is that the strength comes from wood with wood/epoxy. The glass skin is for protecting the wood. With foam sandwich the strength comes from the glass skin, which therefore needs to be thicker compared to a wood/epoxy design. Wood/epoxy scantling is irrelevant if you use a foam core.

    Erik
     

  5. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    You should use the foam core formula.
     
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