Ferro-Cement Multihull Scantlings

Discussion in 'Multihulls' started by DrCraze, May 19, 2010.

  1. DennisRB
    Joined: Sep 2004
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    DennisRB Senior Member

    What ever happened to this project?
     
  2. Corley
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    Corley epoxy coated

  3. oldsailor7
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    oldsailor7 Senior Member

    The really environmental property of a ferrocement boat is that when it goes aground it just naturally becomes part of the reef. :eek:
     
  4. rberrey
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    rberrey Senior Member

    I would venture to say that with modern materials such as composite rebar , kevlar or fiber mesh added to the mix, delvo to put the mix to sleep, a plastersizer added, xypec to make the concrete water proof, we all might be supprised at the end product. I will try to get one of our concrete reps to design a mix and post results. Rick
     
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  5. rapscallion
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    rapscallion Senior Member

    Add Methacrylates to the mix and you have the cheapest bulletproof composite material I know how to make.... and it's my job to study that kind of thing....
     
  6. oldsailor7
    Joined: May 2008
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    oldsailor7 Senior Member

    Back in the late 1960s at the behest of a multihull magazine (now long defunct), my company carried out a range of tests on various ferrous cement structures, using (of course) the materials available at that time.
    After thorough evaluation we decided that, except for large heavy displacement monohulls, it was not suitable for the stiff, light displacement structures needed in multihull sailboats.
     
  7. rberrey
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    rberrey Senior Member

    I agree that cement would not be light weight. But with a mix using composite rebar and mesh, added chemicals , I think you could have a thinner , stronger , and lighter hull than you could have produced in the 60s. Such a mix could expand the type boats ferro cement would be suitable for. Rick
     
  8. rapscallion
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    rapscallion Senior Member

    Even with superglue, cement has poor tension strength. The awesome compression strength is what makes it impact resistant. Can you build a multi out of it? Yes. But I still feel the best way to go is epoxy and wood. Adagio is over 40 years old, and is still one of the fastest boats on the great lakes. But if you want to build a cheap bulletproof house, use concrete, foam and superglue.
     
  9. rberrey
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    rberrey Senior Member

    I,m a concrete man and wouldnt build my trimaran out of ferro, but a new mix with modern materials could give an affordable option to someone . Rick
     
  10. tugboat

    tugboat Previous Member

    May i ask what the steel content was?..how has it been so far? sea trials?--im still doing a ferr-cement pressure hull in my sub see its progress at http://www.youtube.com/user/porpoisefathom?feature=mhee
    mesh or bird netting|?/i like using a polymer modifed cement-called mg krete--it has a 9500 psi compressive strength after 28 days with no water curing...http://www.imcotechnologies.com/canadian/canadian.html- data sheet- concrete repair- 1260 mg krete
    thanks!
     
  11. rberrey
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    rberrey Senior Member

    9500 psi sounds good, what is the weight cu ft? I would look into carbon rebar or composite mesh in place of mild steel if I were doing a build with cement. Rick
     
  12. Liquidoverhaul
    Joined: Apr 2016
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    Location: Mackay

    Liquidoverhaul New Member

    Hi sorry for posting on such an old thread but just wanted to share with steve w that i have recently just purchased a ferrocraft 40 in mackay australia after researching the vessel i found his post on here and the boat might be 44 years old but is still holding up well if you see this steve send me an email at liquidoverhaul at gmail.com
     
  13. redreuben
    Joined: Jan 2009
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    redreuben redreuben

    So a plaster and lath boat in effect ! Wow, well 45 years or so is pretty good proof of concept, liquidoverhaul your a brave man I think, it would still spook me !
     
  14. Manfred.pech
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    Location: EU

    Manfred.pech Senior Member


  15. Manfred.pech
    Joined: Apr 2010
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    Location: EU

    Manfred.pech Senior Member

    Very interested to lern more about the results. M.
     
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