Daggerboard protection

Discussion in 'Sailboats' started by Herk_Man, May 12, 2013.

  1. Herk_Man
    Joined: May 2013
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    Location: Oklahoma

    Herk_Man Junior Member

    Hi all,

    I am making a new daggerboard for my 1969 Chrysler Barracuda. I think I'm going to use teak. 2 questions: (I'm a proficient woodworker but low experience making things that will be exposed to water.)

    Do I need to overlay the wood with fiberglass to protect it or is the natural water resistance of the teak enough? The daggerboard will only be in the water when sailing.

    I'd also like to make a metal tip for the daggerboard so that I don't damage the teak whenever I come into shore. The lake where I sail has an irregular bottom so it is impossible to judge when it's time to pull the board.

    Anyone ever constructed a daggerboard this way? Am I just nuts?

    Thanks!

    H
     
  2. Landlubber
    Joined: Jun 2007
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    Landlubber Senior Member

    Millions of boards were constructed this way mate, go for it.
     
  3. Richard Woods
    Joined: Jun 2006
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    Richard Woods Woods Designs

    I wouldn't use teak, and I don't know anyone who does. Douglas fir or mahogany are more common woods to use if you laminate them. No need to glass sheath a daggerboard that is not in the water all the time

    Richard Woods of Woods Designs

    www.small-boat-designs.com
     
  4. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    Not the least bit "nuts" Herk.

    You can use teak if you like, but other less exotic wood will work as well. White oak, Ash, Yellow pine, etc. Teak is often kind of oily. If so it will not be the best wood to apply glass or to laminate. Much of the teak is also abrasive and it kills the nice sharp edge you used to have on your plane or saw blade.

    I would use a glass/epoxy sheath to give the board, not the teak board, a little bit of protection. You can use something like 3/16 inch round rod of stainless, brass or aluminum for the leading edge and tip. Epoxy it in place and then cover the whole thing with six or eight ounce glass. Do not make the trailing edge sharp. If you do, it is too vulnerable and the flatter trailing edge will not hurt performance much.

    Be careful that you do not make the board too thick. It should slide easily but not sloppily into the case. Measure the slot warily before you finish the board.

    You may want to add a slug of lead or something heavy imbedded in the lower end of the board. Just enough weight so that the board does not try to float upward in the case. This happens when tacking or otherwise relieving side pressure on the board. You can also hold the board down without the lead by using a wedge at the top opening of the case. A rubber wedge shaped door stop works good for that purpose. The weighted board is more convenient than using the wedge but the wedge is still useful for holding the board in semi retracted position when sailing downwind. Spend some time finishing the wetted surface of the board nice and smooth.

    Good luck and have at it.
     
  5. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    I agree with Richard, teak wouldn't be my first choice, though if wood, I'd make a vertical laminate of softwood, Douglas fir, SYP or other moderately dense stock.

    It doesn't need to be sheathed, though the trailing edge and the bottom edge will need some protection in the event of strikes and groundings. This could be as simple as a length of metal bar stock or rope, set in a groove - to epoxy grout with pulverized granite dust as the filler.
     
  6. michael pierzga
    Joined: Dec 2008
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    Location: spain

    michael pierzga Senior Member

    Whoa...! Teak, you must be a banker !!!!


    Lightweight, stiff, straight grain wood , that glues well is a better and cheaper way.

    Check with your local lumber yard for wood suggestions.

    Also have a look at http://www.westsystem.com/ss/

    West epoxy web site for build suggestions.

    Perhaps its in their magazine " Epoxy works"
     

  7. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Try this list of their publications:

    http://www.westsystem.com/ss/techniques-materials/

    . . . or:

    http://www.westsystem.com/ss/assets/HowTo-Publications/GougeonBook 061205.pdf

    for their book on boat construction, which covers a few different methods.

    The vertical strip planked technique is commonly accepted and far better then a plywood laminate, though a little more effort. A cored composite is a choice, which can be inert (my preferred method) and not suffer the ills of wooden blades. A solid wood board also isn't recommended, because of warpage and the difficulty in finding suitable stock.

    [​IMG]

    Since the board of this boat isn't highly loaded, you can use pretty much anything you want, but a durable, stiff and easily shaped appendage is desirable. If it was me, I'd make a foam core composite, but if forced, I'd do the vertical strip planked laminate.
     
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