Mixing similar designs

Discussion in 'Boat Design' started by Paul No Boat, Feb 10, 2010.

  1. Paul No Boat
    Joined: Dec 2009
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    Location: Indiana

    Paul No Boat Junior Member

    I have admired this boat, The Flanders Cat for awhile. I love the elegant look of Lapstrake. http://www.sailblogs.com/member/flanderscat/

    I have not found a set of plans for it. John D. Little who designed her is deceased. (rest his creative soul)

    However I have been Emailing with Ted Brewer about his Cape Cod Bay, a boat of similar size and purpose.


    Mr brewer's design is to be built as a vee hull plywood over sawn frames. I suggested as to lapstrake planking over the plywood for appearence and Ted corrected me on it as the laminated construction would create pockets of moisture and promote rot.

    His suggestion instead was to cover the bottom of the vee in plywood and lapstrake it from the chine up. When sitting in water an observer would not see the transition.

    I wonder if anyone has any thoughts on mixing designs like this. and is the difference in performance and handling of a vee hull vs round hull significant enough to sway it one way or the other?
  2. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    Lapstrakers are salty looking and the Flanders cat is about as salty as it gets. There are some advantages to this method of construction. The skin can be a bit thinner than smooth skinned boats, the strakes can be coaxed into moderate compound curves that would be impossible with flat sheets. There are downsides to the method like having all those near horizontal little shelves on the interior of the boat. Better to collect dirt, mildew, and make the interior and exterior harder to clean. Then there are all those bent frames who also harbor hiding places for dirt, vermin, and rot. If the build is to be clench nailed or rivet and roved, then it is labor intensive. If glued lapstrake then there is not so much of a hassle.

    I can not remember whether it was Thompson or Lyman who used machine screws and nuts with washers to join the strakes. Whichever the builder it was a bad idea that was surely a product of satan himself. The builder would cut off the protruding ends of the machine screws with a bolt cutter leaving vicious sharp edges with which to lacerate the innocent occupants. Owners of such boats spent a lot of time grinding of the offending sharp edges. Clinch nails or rivets can have a similar effect if not carefully done.

    In spite of the possible difficulties I would not abandon the lapstrake idea. If you choose that hybrid construction, you will need to consult closely with Ted Brewer or other designer that you might use.

    It can be argued that lapstrake boats have more inherent drag than smooth skinned ones. The strake joins must surely create some turbulence not present on a smooth skin. Maybe so, but maybe that is not a major deterrent. Generally speaking a round chine shape has a little less drag than a hard chine. At least at low speed. In spite of that generalization, we see that some of the fastest boats have hard chines. Go figure. Lapstrake worked for the Vikings and much later Chris Craft built some very good power boats, in the 30 foot range, with that method.
  3. Paul No Boat
    Joined: Dec 2009
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    Location: Indiana

    Paul No Boat Junior Member

    Thanks Messabout,

    This would be done almost more as an art project than a highly tuned yacht.
    The Flanders Cat is just so dang pretty.

    Considering the area in which I live, it would never be used in a regatta or race but rather for floating about on weekends and something to show off at the local woodworker's guild. Yet still I want something that is practical.

    I am sure if one looked far enough he could purchase or make lapstrake panels that would give the appearence, but I don't want to build a phony boat either. I am just not into getting too involved with small detail which means the world to a competition sailor but would not even be noticed by a weekend lake or river cruiser.

    The points you made about fastenings and sharp edges is very relevant. Thanks. I am thinking of the Lapstitch construction I recently saw in which the strakes are tied together and then glued along the seams. So trimming that copper wire would be a very labor intensive but important step.
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