A Different Tradition of Innovation

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David Ryan

David Ryan is a boat builder and USCG licensed master captain. He is the owner of Sailing Montauk and skipper of Montauk''s charter sailing catamaran MON TIKI You can follow him on Twitter @CaptDavidRyan

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7 Responses

  1. Avatar Max L
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    says:

    Really enjoying these posts.    I grew up just across the Sound from Montauk, in Essex, CT, where my father managed the Essex Boat Works in the 70’s.    And in a great coincidence, your posts on Mon Tiki started the same week as my plans for the “Cartopper 15” arrived from “Dynamite” Payson.  I gave them to my Dad as a Christmas present and we are picking up the last of the materials (the plywood, in fact) in Berkeley tomorrow..

    I came out to California after college and worked as a carpenter restoring Victorians in SF for a few years…it’s the best carpentry work there is on the West Coast, IMHO.  Pops, of course, taught me my way around the business end of a hammer, saw, and plane when I was a teenager but we never got around to working with fiberglass or bending wood until now.   These days, I am the hands and back of the operation and he is in his true fatherly comfort spot: supervision of said hands.

    Anyway, great posts, keep them coming!

     Report

    • Avatar David Ryan in reply to Max L
      Ignored
      says:

      The Cartopper is a lovely boat. I nearly went for it for my first build, but the tack and tape method was more intimidating than the original instant boats, so I built a Teal instead. My copy of Payson’s Instant Boats is inscribed “Happiness is building your own boat!” Ain’t it the truth, ain’t it the truth.Report

  2. Avatar DensityDuck
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    says:

    As I understand it, the use of carbon fiber / polymer resin structures actually got started in the sporting-goods industry.  It was originally developed by the aerospace industry but was too expensive (due to the limited market).  Fortunately, manufacturers of tennis rackets and golf clubs realized that the material had the combination of stiffness, strength, and weight that they were looking for, and the market they represented resulted in a lot of development in that area.

    The old guys in the shop here tell stories of how the fiber material used to be so brittle that it wouldn’t even bend; it was delivered in flat sheets on the back of a truck, and you could only make flat panels with it.  The idea of graphite cloth is relatively new (and thank God it showed up, because things are a lot easier!)

    *******

    “In cold-molding the wood veneers are saturated in epoxy resin; in plywood the veneers are laminated under pressure using a heat-activated glue that does not penetrate as deeply into the wood.”

    That objection doesn’t make sense. An operation that takes place under heat and pressure will get far better consolidation (squeezing the layers together, pushing out air bubbles and voids) than cold-molding (which has the pressure applied at discrete points and doesn’t use a vacuum bag.) And, as you point out, a factory will have a much more consistent product due to its process control, something that a hand layup done by (relative) amateurs isn’t going to achieve.

    The reviewer does make a good point about the fiber orientations being different. That said, running the fibers longitudinally is going to produce a much stronger structure–it’s like rebar in concrete, you put it straight up and down and not angled sideways.

    Of course, as you’ve found out, test data holds trumps.Report

    • Avatar David Ryan in reply to DensityDuck
      Ignored
      says:

      The objection makes sense if you parse it from a regulatory point of view.

      His point wasn’t that the difference between plywood and cold-molded was so great that it suggested that plywood might be weaker than cold-molded laminated plating; it’s that the two were sufficiently different that he felt the standard for one couldn’t be substituted for the other. Any review process is going to have areas that call for the exercise se of judgment and discretion, and given the difference, even if those differences suggested that plywood might be stronger, they were simply too great to say “No problem. Go ahead and use the cold-molded formula. I’m sure that’s what ABS would tell you to do.”.

      The larger point is that absent empirical tests, there is no rule for plywood, which is a pity, because it’s an excellent material for building boats (or airplanes.) But the category is simply too small for ABS to take an interest.Report

      • Avatar DensityDuck in reply to David Ryan
        Ignored
        says:

        I agree with him that the methods and processes differ to the point that the standard for cold molding should not be applied to laminated plywood.

        The blog post seems to imply that he was concerned it would be weaker.Report

        • Avatar David Ryan in reply to DensityDuck
          Ignored
          says:

          Quoting:

          “He agreed that our argument was not unreasonable, and believed it would be supported by testing data, but he felt he could not approve the argument under the cold-molded rule for two reasons:”

          Report

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