Frameless Construction

Discussion in 'Sailboats' started by Scylla, Sep 5, 2005.

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    FAST FRED Senior Member

    For any cruising boat construction with a core (Airex is probably the best) is more desrable than solid construction.

    IF the core is NOT used to create a super lightweight hull and the normal glass boat scantlings are used , the stiffness becomes unreal.

    Here in the US the USCG does not count the deck as part of the structure on working hull stiffness for inspected boats.
    In otherwords the "teacup" of a hull must be stiff enough, required is 400%.
    Which means the hull virtually never flexes.

    A small cruiser could have 1/2 in of solid glass and be fine ,
    BUT when the layup is split and a core inserted 1/4 glass 3/4 Airex and 1/4 glass the stiffness becomes unbelievable !

    Foam cores are OK as insulation , not GREAT!! but definatly a huge help.

    I have enjoyed a NYC winter aboard where the outside temo got to -17F , and was able to enjoy a T shirt enviroment inside with only a 20,000 BTU Dickinson range as cabin heat.

    The Disadvantage to a Quality foam core is ONLY the inital cost.

  2. Wynand N
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    Location: South Africa

    Wynand N Retired Steelboatbuilder

    I built a few v/d Stadt 34 / 40ft hulls. D'Artios is quite right. The plates are developed prior to installation - all three chines plates (half side) are joint to full hull length, marked & cut, then installed within a frame and pulled together and tack welded. This method is fast and easy, I produced a 34 ft hull & deck in 18 working days flat, blasted and prime painted.

    I attach two photos of this frame and plating method by v/d Stadt.
    In photo one plating is installed in building frame and tack welded together.
    In photo 2 the same hull with deck installed sans keel - incidently, it is a 34ft "Norman", custom built by yours truly, based on the 40 ft Norman.
    Third photo with the three hull shows a frameless raduis chine hull on the left. This is a 38 ft hull and living proof that a fair raduis chine hull can be build frameless ;)

    Attached Files:

  3. Bas van Deursen
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    Location: Holland

    Bas van Deursen New Member

    Stadt 34

    Hi there,

    I'm writing this from the Netherlands. The Water County ;). I own the complete set of registred plans of the Van de Stadt 34, steel version. Whit these plans it is simple to build your own brand new 34. I wanted to build it my self, but i had to change plans. We wanted to sail quickly instead of a few year of building. I am a father of three, so thats why we bought a Dehler Optima 106, of the same designer, mister Hans Korner (van de Stadt design)

    For now i am considering to build a larger sailyacht, a bruce roberts design, the voyager series are perfect!

    Perhaps you are intrested in the plans, it will be a lot cheaper to buy. My plans are fully supported by the van de stadt design office, and officially registrated whit a unique hull number.

    The stadt 34 is a very strong yacht, easy to build and easy to adjust to your own wishes.

    Bas van Deursen
  4. Bas van Deursen
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    Bas van Deursen New Member


    To: Wijnand N, Afrika

    i have seen your building site, looks nice

    Do you build professionally or for the fun of it?
    I have a set of builing plans and a registrationnumber i want to get rit of...

    First i wanted a Stadt 34, but now i am considering a Bruce Roberts Voyager.

    Perhaps you can use my plans...Special price of course ;)


    Bas van Deursen
  5. Wynand N
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    Location: South Africa

    Wynand N Retired Steelboatbuilder

    Hi Bas,

    Thanks for the offer, but I got rid of my copies of the Stadt 34 and Stadt 40 Carribbean/Norman plans.
    In fact, I swopped it for a book or two :cool:
  6. Scarmari
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    Scarmari New Member

    I am in the final stages of re-plating the bottom of a 40 year old steel yacht. She is a 30ft Alan Buchanan designed sloop. She has cruised the from the Norwegian Arctic to the river Plate and from Panama to the Bosphorus. Strong and seaworthy in spite of being caught between fishing boats in a hurricane which necessistated cutting out her sides amidships and replacing them. She is insulated with polystyrene loosely fitted between the frames and with cork glued to exposed surfaces and painted. Below the waterline, and below the insulation however she is corroded right through in places as the through ventilation condenses moisture out of warm humid air as it contacts the sea temperature steel. My advice would be that you should insulate and pay particular attention to below the water line. Rockwool sealed in plastic bags, cork or polystyrene are all effective and relatively cheap. This should be accompanied by good ventilation.
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    D'ARTOIS Senior Member

    Could that be the boat of Tristan Jones? That must practically be the case, if not, I would be very interested to know the name of her owner who followed alomost the same path of the late Tristan.

  8. brian eiland
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    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    I wanted to bring this subject thread back to life, as I intend to post some related discussions
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