Single Dagger Board vs Double Boards

Discussion in 'Multihulls' started by CatBuilder, Apr 26, 2011.

  1. mikereed100
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    mikereed100 Junior Member

    I really don't think a single board would affect resale of your boat much. The buyer who would be put off by a single board is probably going to be looking more at production cats anyway. Those looking at a custom boat have likely already evolved beyond 4 heads, a flybridge and those cool little seats on the bow pulpits. The buyer with an open mind (the one looking at your boat) may well be intrigued by a novel concept, so while it may take a little longer to find a buyer with properly refined tastes, it shouldn't affect the final price. But what do I know, I'm not a broker.

    Anothert thing to consider is that while you will sell it someday, this is your boat. Screw the boat buying public and make it the way you want it.

    Mike
     
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  2. oldsailor7
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    oldsailor7 Senior Member

    IMHO if you are sailing a cruising catamaran which is not expected to lift one hull out of the water, one board is quite sufficient providing it is of the right size.
    After all, monoplanes superceded biplanes because they were more efficient.

    Tripping shouldn't be a problem. If you were lying a-hull in severe wave conditions, or sailing DDW, you would have all the boards up anyway.

    I also can't see why having only one board would deter a prospective buyer unless he was a complete noob who didn't know much about sailboats, but had fixed opinions. :eek:
     
  3. cavalier mk2
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    cavalier mk2 Senior Member

    And fixed opinions con be worse than affixed keels!!
     
  4. keysdisease
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    keysdisease Senior Member

    It is true that later MacGregors cats had two boards. Because they were marketed as performance boats I always assumed this was a performance issue.

    From a strictly objective point of view there has to be a difference in leeway prevention / windward ability between one and two boards. If executed correctly (properly sized single board) this disparity can be minimized, but will still exist.

    And I'll bet just like I did with my own MacGregor that Catbuilder will be the only one that ever notices the difference between one tack and the other.

    Of course, this only matters when the wind is forward of the beam so just end this fence sitting and always sail with the wind aft of the beam.

    Simple, Steve
     
  5. CatBuilder

    CatBuilder Previous Member

    :D:D

    That is the only way to go, isn't it? :)
     
  6. keysdisease
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    keysdisease Senior Member

    Well, Duh, of course. :p:p:cool:

     
  7. rayaldridge
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    rayaldridge Senior Member

    My reading of the evidence suggests that a large single board will have more lift and less drag than two smaller boards. I wish we could get Tom Speer to comment on this.

    Steve, I know you were kidding, but I got to thinking about it, and if you limited your sailing to wind aft of the beam, in a fast multihull, there wouldn't be many courses you could sail, would there?
     
  8. catsketcher
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    catsketcher Senior Member

    Just watched the AC 45s doing their thing on a video. One thing that struck me was that they have one crew whose job its seems is to pull the boards up and down. Only the leeward one seems to be down at any one time. Their boards are big and they slide up and down with incredible ease its seems even with side loads but these guys certainly don't worry about symmetry. It seems fast to go with one board if it is well immersed or to leeward. That is the real question - Is a board being to windward (if not flying a hull) any worse than being to leeward? It certainly seems as though a single board to leeward is the fastest according to these fab sailors.

    cheers

    Phil
     
  9. oldsailor7
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    oldsailor7 Senior Member

    Food for thought Phil.
     
  10. sabahcat
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    sabahcat Senior Member

    Nothing to do with sailing ability but on my last cat, when at anchor, I had a large tarp strung under boom to almost deck edge providing shade for cabin and keeping rain off

    This was attached to top of daggerboard.

    How would I do this with only one board?
     
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  11. keysdisease
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    keysdisease Senior Member

    As catsketcher said, even when I was racing beach cats, the leeward board is the important one. Key word being "racing"

    And yes ray, I was kidding. :) You are more than correct because in a fast cat the apparent wind is often forward of the beam.

    Steve


     
  12. cavalier mk2
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    cavalier mk2 Senior Member

    The main thing with one board is that the structure support it on both tacks, some of the racers boards are designed for bigger loads on leeward tacks and often do sail with just the leeward board for less resistance. If you are sailing with one board with both hulls in the water you have a asymmetrical set up and the boat won't care if it is to windward or leeward the lift will be the same minus the few inches lost when the board is to windward and the lee hull is depressed by the wind load. Someone email Shuttleworth.
     
  13. oldsailor7
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    oldsailor7 Senior Member

    John Hitches "HitchHiker", a modified Crowther Spindrift 45, had two assymetric boards.
    One morning at dawn we were entering Broken Bay on the way back from Lord Howe Island in a light header. I was just at the end of my watch and the crew was still asleep below. I had both boards down for max leeway prevention, when John came up on deck and gave me a right royal tick off. "Don't you realise that with both assymetric boards down one is cancelling out the other".
    I couldn't convince him that both boards worked to help reduce leeway even though the "wrong" one was doing it less efficiently. :p
     
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  14. rattus
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    rattus SeƱor Member

    Actually, with a multi of sufficient performance, the wind would *always* be forward of the beam. ;-)

    I don't think the AC33 multis or the new AC34 "short cats" ever experience an aft-of-beam condition unless docked.

    Mike
     

  15. Dryfeet
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    Dryfeet Junior Member

    Not to be argumentative but if you had two boards on a Mainecat, it wasn't a 30 footer! Could only have been a 41.
     
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