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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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18 Responses

  1. Avatar James Hanley says:

    Breech birth, eh?Report

  2. Avatar Chris says:

    Is it strange that my first thought upon seeing the picture on the front page was, “Where are pairs of all the animals?”Report

  3. Avatar James B Franks says:

    looks great! heh I can’t believe how different you look without the beard.Report

  4. Avatar Kazzy says:

    Can you explain in layman’s terms what you said in that last paragraph?Report

    • Avatar David Ryan in reply to Kazzy says:

      MON TIKI is being built under T-Boat regulations. The same CFRs that govern the Staten Island Ferry govern the design, construction, and operation of our catamaran.

      The akas (crossbeams) that connect our catamaran’s two hulls are connected to the hulls using the traditional Polynesian method of lashings. This creates a tough, resiliant, inspectable and replenishable connection.

      This method has been used in Polynesian craft for years, and is a hallmark of James Wharram fleet, but never in a T-Boat. We had to provide engineering data for the design and that data had to be reviewed and vetted by the US Coast Guard Marine Safety Center Small Vessel Detachment. More than a few people thought the Coast Guard would balk at the idea of holding a boat together with ropes.

      But they didn’t. We made our case with safety margin of nearly 5:1, and our local inspector was especially impressed with how easily this vital aspect of the boat can be inspected and maintained before problems start.

      It also meant we could build a 21 foot wide boat in a shop with a 12 foot wide door!Report

        • Avatar David Ryan in reply to BlaiseP says:

          The turns going around the bundle are called “frapping turns” and create tremendous compressive force. When combined with modern rope, the strength easily exceeds what might be achieve with metal fittings of the same weight, or GRP moldings, but all the work can be down with Grandma’s knitting needles.Report

          • Avatar BlaiseP in reply to David Ryan says:

            The physics of rope technology are extraordinary. The Romans were masters of rope and used it in catapults as well.

            What kind of ropes did the Greeks and Romans use?

            The Romans and Greeks probably used horse hair, and when there wasn’t enough of that, it has been said that they used human hair. Everyone in an entire township would have to shave their heads for the war effort. The hairs would be spun into ropes, and bundled together to make skeins of hair about 1 foot thick and several feet long.

            There is actually some debate about this among historians. Some believe that animal sinew and even leather was more likely used. But the ancient people were pretty smart about natural materials, and from an engineering perspective, hair is a better material. It’s also a lot easier to get in rope-making quantities than sinew.

            In fact, hair is actually much stronger than steel in a pound-for-pound comparison, and it is also extremely elastic. It was, and still is the best thing around for powering Onagers. Modern reconstructions of Onagers typically use nylon and polypropylene ropes. These are good choices, but are still inferior to bundles of hair. Report

  5. Avatar Mark says:

    David,

    Any chance you still have any Catalina 38 steering parts? I’m converting from tiller to wheel and need the radial drive, rudder stuffing box, and adjustable cable idler.Report

    • Avatar David Ryan in reply to Mark says:

      My god, man! Why on earth would you switch a Catalina 38 from tiller to wheel steering! When I got my C38, one of the first things I did was take the wheel out!Report

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