Discussion in 'Sailboats' started by greenwater, Aug 5, 2008.

  1. Jim Bates
    Joined: Nov 2018
    Posts: 8
    Likes: 0, Points: 1
    Location: Slidell, La

    Jim Bates Junior Member

    First, I am aware that this thread is quite old, but am hopeful that I can locate Bataan, and his boat, Bertie, if anyone can supply contact info. I have purchased a Bruce Robert’s Spray 38 design, very well built in steel by an excellent welder to a high standard. The rig is a gaff rigged cutter, to which I am adding a mizzen to convert to a yawl rig. I live in South Louisiana in a light air environment, and the SA/Disp ratio is only 12. I am interested in increasing the size of the main, to the max practical, ala Bertie, and would like to discuss this matter with Bataan, and if he agrees, examine Bertie in person, to see if his junk rigged main could be converted to a gaff rig. My email is jimb522@yahoo.com. I am also perfectly willing to do it in this forum. Thank you for any help.
  2. Angélique
    Joined: Feb 2009
    Posts: 3,003
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    Location: Belgium ⇄ The Netherlands

    Angélique aka Angel (only by name)

    Hi Jim, here some videos featuring Bataan's BERTIE, she's at least in the below part 1 and 3, haven't seen them all myself yet, will watch later...

  3. Jim Bates
    Joined: Nov 2018
    Posts: 8
    Likes: 0, Points: 1
    Location: Slidell, La

    Jim Bates Junior Member

    thank you angelic.
  4. Schoolbus
    Joined: Mar 2015
    Posts: 10
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    Location: Ontario

    Schoolbus Junior Member

  5. sharpii2
    Joined: May 2004
    Posts: 2,249
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    Location: Michigan, USA

    sharpii2 Senior Member

    I read your piece with great interest.

    The VCG of the original SPRAY, in its final rig format (as a yawl) may not have been high as you think. Once he crossed the Atlantic twice, he actively reduced his sail plan. First, the Boom had already been shortened, due to an encounter with a rogue wave. He next cut a great deal of length off the mast and shortened the bowsprit, converting his head sail arrangement from a two jib one to a single jib one. Even this lowered the VCG somewhat. Now he had gone down from around 1,300 sf to around 900.
    It was some time later that he added the 155 sf mizzen, which raised the VCG (but not nearly as much as shortening the mast lowered it)

    Even though I doubt that the keel had any ballast in it, it was most likely made of unseasoned timber, so was already totally saturated, so had a considerable amount of water ballast in it. So too did the bottom frames ad floors. It is unclear to me whether he raised the deck or just merely raise the height of the bulwarks. Then, there is no mention of how much concrete was added to the bilge. I wouldn't be surprised if it was in the order of 5 tons or so.

    I think the true capsize vulnerability came more from the proportions of the maximum water tight section than from weight distribution (although a huge lead slug in the keel would sure help).

    By improving this boat, you have created a much larger one.

    I would keep the length and draft the same, but dock the Beam by about 2 ft and end up with a displacement of around 13.75 tons. I would raise the deck to just 3 inches below the sheer. And I would put most if not all the ballast in the keel. I would pare the thickness of the mast down to maybe 8 inches.
    And I would do little else.

    I would tolerate a lower Stix as long as it was a passing number. This is because the shape of the hull, it's weight, and it's long keel, make it much harder to knock down than a much lighter, deeper keeled, and taller sail plan modern yacht.

    I would resist the temptation to increase the sail plan, as I would have to go taller, and I would worry about the heeled CE of the sail plan ending up too far to the Lee of the hull. Besides, I believe a smaller sail plan does not hurt a heavy boat as much as it does a lighter one.
    Besides, I would now have a lighter boat because I docked the Beam to 12 ft. I estimate I would end up with an S/D of around 17, which shouldn't be too bad.
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