masthead cutter design ?

Discussion in 'Sailboats' started by frank smith, Oct 1, 2009.

  1. frank smith
    Joined: Oct 2009
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    frank smith Senior Member

    Hi , I have been working on a small cutter design .
    At this point I am thinking about the rig , and the amount of lead that should
    it should . Also any input about the rig would be appreciated.

    Frank
     
  2. frank smith
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    frank smith Senior Member

    Sorry about that . I am interested the amount of lead it should have , I know that about 10% is a standard stating point.

    Frank
     
  3. Raggi_Thor
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    Raggi_Thor Nav.arch/Designer/Builder

    It depends on your heeling angle and height of the rig.
    Thats what turns the boat towards the wind and must be balanced with the lead.
     
  4. lewisboats
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    lewisboats Obsessed Member

    Yes and no...a lot depends on the hull shape, the keel design, the length of the hull (what is 'small'?) The more balanced the hull the less it changes the water shape as it heels and the less lead you need. A full long keel will need different lead than a narrow. deep, high aspect ratio keel. A small (less than say 20 ft) light weight skiff will change the water shape as you move around and will be more sensitive to weight change than to actual fixed lead of the centers.
     
  5. Raggi_Thor
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    Raggi_Thor Nav.arch/Designer/Builder

    Well, I think this is overlooked and mystified quite often.
    Look at the boat from behind when it heels. You can estimate the arm between the sail's center of effort and the boat's center of resistance. Wide shallow boats have a short arm (or even negative) while narrow deep boats have a long arm.
     
  6. PAR
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    PAR Yacht Designer/Builder

    12% to 15% would be typical, more if the rig is tall, the hull shallow and the appendages refined. Of course a sketch of your sail plan and hull profile would be helpful.
     

  7. frank smith
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    frank smith Senior Member

    Thank for your replies , I am still in the planing stage but will put some info
    in a usable form as soon as i can .
    thank again

    Frank
     
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