Forward angled bulb keel

Discussion in 'Sailboats' started by waterworld, Oct 19, 2007.

  1. waterworld
    Joined: Mar 2007
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    Location: Nashville, TN

    waterworld New Member

    I am wanting to modify a home built 20 foot lifting keel sailboat so that the bulb keel centerboard casing is situated in the cockpit rather than intruding into the cabin.

    I have recently seen some pictures of forward angled bulb keel designs where the keel rakes forwards rather than aft. Are there any design considerations/problems I should be aware of? If the bulb itself essentially remains in the same position, other than the weight of the keel can I assume that the CG will remain the same. This would seem to be a good solution to relieving cabin clutter.
    Many thanks,
    Mark
     
  2. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    If you move the top of the fin aft, then angle the bottom of the fin forward, you have moved the center of lateral area of the fin. If you have not moved the mast aft you will likely have some lee helm. That is not good. In some cases, lee helm is dangerous. In almost all cases it will reduce your ability to go to windward. A modification of that type will necessitate other changes that you may not wish to do.
     
  3. bart streb
    Joined: Oct 2007
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    Location: North Carolina

    bart streb Bart

    Is this a true lifting keel, that raises straight up, or a swinging keel? If it is a lifting keel, I could imagine the difficulty raising it at an angle, the stress involved, and not to mention, the angle would require some sort of rigging in the cockpit to raise, increasing cockpit clutter.
    A picture of your boat would help.
    I would suggest some sort of fixed keel, a short shoal keel, unless you are performance minded. I will have a 400lb+/- keel available soon on in NC (maybe we could swap??). It is coming off a 21' boat. That would really clear up the clutter.
     

  4. SAE140

    SAE140 Guest

    Apart from the shifted CLR issue which has already been mentioned, a forward raking keel will have a tendency to collect floating material - seaweed, plastic sheeting, rope and similar garbage.

    Colin
     
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