new hull form for catrigged boat

Discussion in 'Sailboats' started by adriano, Jun 20, 2012.

  1. adriano
    Joined: Aug 2009
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    adriano Senior Member

    Hi there,
    I found on the web this cat rigged boat.
    Never seen before such a hull for a cat.Can anybody confirm that the entrance
    has a kind of trimaran shape??!!:rolleyes:
    If it's not matter of a light reflextion, apart from more stability, would this
    contribute to push back the center of lateral resistance which is an issue on a wide beamy boat?
    See attatched picture
    It would be interesting to know somebodyelse's opinion.
    Thanks
    Adriano:)
     

    Attached Files:

  2. davhill
    Joined: May 2012
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    davhill Junior Member

    Trimaran shape? What are you smoking?
    This is a catboat, not a catamaran. A catboat is a traditional hull of wide flat form, usually centerboard, with beam typically half of length,and with a single mast mounted far forward. Almost always gaff rigged with no jib. They developed as working sail for the shallow waters around Cape Cod and Long island sound, but are now usually pleasure craft. See Beetle Cat for another common example.
     
  3. gonzo
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    gonzo Senior Member

    Yes, it is a monohull of a traditional type. The bottom is a bit flatter than usual though.
     
  4. Dryfeet
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    Dryfeet Junior Member

    I can see where the shadows on the hull may have confused the OP. However, this is indeed a traditional catboat. The hull shape seems to be a bit of an updated sandbagger type hull. It does look a bit flatter than usual.
     
  5. adriano
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    adriano Senior Member

    Yes of course Iknow what is a catboat, I mentioned trimaran "kind of entrance shape!" because of my poor english knowledge
    You have to agree that picture shows something different unusual at least for my experiences. may be you didn't notice it?!
    Adriano
     
  6. adriano
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    adriano Senior Member

    Yes, I agree that's all about, the reflextions are confusing a bit the shape.
    I was wondering too, may be somebody could have done a prototype?!
    Adriano
     
  7. adriano
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    adriano Senior Member

    right,
    adriano
     
  8. davhill
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    davhill Junior Member

    LOL. Ok, I see the shadows /reflections of the black support beds are deceiving. My apologies. Yes, an unusual hull even among cats. Very slick.
     
  9. adriano
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    adriano Senior Member

    cat boat modeling

    Hi there,
    I would very much appreciate any comments whether sofar anything wrong with the following diamentions.:confused:
    Am trying to model Gil Smith's Lucile kind of catboat with following
    measurements (of my actual model):
    LOA mt. 5.0
    LWL mt. 4.4
    Beam wl mt. 1.333
    draught mt. 0.15
    Cp 0.457
    Long. Center of Buoyancy -1.479
    skeg/rudder and centerbaord have to be added of course.
    That's the best I could achieve, indeed trying to bring back the CLR
    in order to avoid strong wheather helm typical for beamy boats.
    On one hand I wouldn't like to change too much from the original beautiful
    lines of those traditional catboats.
    Many thanks in advance for any suggestions/improvements.
    Adriano
     

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  10. gonzo
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    gonzo Senior Member

    Catboats are usually beamier. Also, they carry the beam far forward to accommodate the mast.
     
  11. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    The hull form modeled there, wold typically be referred to as a freak and not to be taken very seriously, for obvious reasons. How did you come about to develop lines of those proportions?
     
  12. messabout
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    messabout Senior Member

    I presume that the middle drawing is the curve of areas of your boat. You will surely wish to change the lines of the boat so that the area distribution is a lot closer to the curve of a conventional boat. A layout like the one you show will cause the boat to be most inefficient. To put it bluntly, it will be a dog.
     
  13. Gary Baigent
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    Gary Baigent Senior Member

    If you're going to carry a cat rig right up front, you will need more substance there to carry mast weight and more buoyancy for the sail power to lean onto - and not push the bow down - as will surely happen with your fine bowed design, hard steering will result.
    Your as drawn boat would be okay with a conventional rig stepped further aft, then you could keep your fine and hollow bow, which you obviously like. Also why the overhanging after sections? A true Skimming dish/dinghy-type boat has buoyancy there for downwind planing and also longer waterline length for better windward speed and power to carry more sail. If you're concerned about dragging sterns in light airs, you just shift crew forward and to leeward, which leaves a fine clean wake.
    Yours would be better on a classic long keel boat.
    This 18 foot design carries a double cat rig (sketch) and balances very well, is powerful and fast. Not saying this is the apotheosis of dinghy design but just an example of a similar sized hull to your own.
     

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  14. quequen
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    quequen Senior Member

    Adriano, you are more or less ok on some buttocks of the bodyplan view, but far away on the other views. Check the waterlines on the plan view, they must look weird by now.
    This Gil's beauty is awesome:
     

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  15. Silver Raven
    Joined: Oct 2011
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    Silver Raven Senior Member

    Gooday 'que' - if that boat is in your - ' backyard pond' - be very + + very prepared for a HUGE attack & boarding party - CAUSE - I'm a commin' to getcha - WOW What a beautifull sailing vessel - - such a classic - not 1 bit of wake - or trouble through the water. If only the very 'smart' (NOT) modern designers could EVER do so well ! ! ! WOW - Blinken heck - I wish I could get to sail such a lovely vessel. Ciao, ajmes
     
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