Cruising cat design

Discussion in 'Multihulls' started by Moewaka, Jun 25, 2016.

  1. brian eiland
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    brian eiland Senior Member

    That detail makes the vessel sound really suspicious to me...:!:

    ...polystyrene foam...how would you ever get a proper bond between that foam and the skins :?:
     
  2. bajansailor
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    bajansailor Marine Surveyor

    I also have my doubts about using polystyrene foam as a core. Especially re getting a good bond between it and the plywood.

    There is a photo on this page of Dudley's build photos showing the foam core being installed on the hull side :
    http://www.dixdesign.com/dh550 build5.htm
     
  3. brian eiland
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    brian eiland Senior Member

  4. DennisRB
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    DennisRB Senior Member

    It acts as insulation and makes it look nicer. Stringers make a boat look home made but give the strength not the foam. I expect it gains a some stiffness from the foam and it would make the boat float higher in case of a total flooding.
     
  5. rattus
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    rattus Señor Member

    I corresponded with Dudley Dix about this a few years ago; The outer skin is quite thick and the stringers are sufficient for stiffness. The polystyrene is there simply for insulation, and considering the target market climate, makes sense to me. The inner skin, which is fairly thin, dresses up the interior. Might make a small contribution to stiffness in closing a box beam, but the poly is not intended to be structural.
     
  6. redreuben
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    redreuben redreuben

    Christ imagine all that squeaking in a seaway ! :D
     
  7. brian eiland
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    brian eiland Senior Member

    That might just be true ?:eek:
     
  8. DennisRB
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    DennisRB Senior Member

  9. brian eiland
    Joined: Jun 2002
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    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    Dudley Dix catamarans now available in kit form,...precut panels

    http://www.exocetus.net/
    Why Buy a Kit

    [​IMG]
     
  10. oldsailor7
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    oldsailor7 Senior Member

    Unless you want a "Roomeran" (ie: Piver), then my choice for a fast cruiser for a crew of four, is a Crowther Kraken 40. :cool:
     
  11. DennisRB
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    DennisRB Senior Member

    Don't forget to saw the handles off your razors.
     
  12. oldsailor7
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    oldsailor7 Senior Member

    :?: please explain.
     
  13. DennisRB
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    DennisRB Senior Member

    Serge Testa sawed the handles off his razors so they would fit on board when he sailed around the world on the worlds smallest boat to circumnavigate. The comment was fairly cryptic I will admit :D
     
  14. Mickdh550
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    Mickdh550 Junior Member

    The styrofoam is purely insulation. If you want to see s current build look up”the making of marram” on Facebook. He is doing a fantastic job and is building the 47 foot version Dh470
     

  15. Niclas Vestman
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    Niclas Vestman Senior Member

    I am under the impression polystyrene might work very well. I would love your input in my new thread in the materials forum. Espescialy in a larger cat insulation might be important. Large areas dissipating heat, and preventing condensation. Why not use the extra weight as a structural component? 4" or 100mm finnfoam XPS should be about equal to 15mm H80 Divinycell. Nothing to sneaze at :)
     
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