Preview: TUMBLEHOME – A Designer’s Dreamboat

12 Responses So Far to “TUMBLEHOME – A Designer’s Dreamboat”

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  M. R. Macy says:

  Intriguing, sleek, with what appears to be an extremely comfortable layout & innovative design choices. Certainly made my morning !

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  Andrew Shemella says:

  I love the innovation in design all around the boat! And I would appreciate another video dedicated to that skiff.

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  Alan Stannard says:

  Thank you, she cuts the water beautifully, I like the dinghy on the fire deck, it appears the two sections can be bolted together to make a suitable length to suit the whole family.

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    SCOTT SPRAGUE says:

    Yes, the skiff is a catamaran, 15′ long, 4′ wide, where the forward 7′ detaches and fits into the aft 8′ for storage on deck. It’s not a sailing catamaran…it slips along nicely with single or double rowers, or a small outboard makes it fly. The deck storage is just high enough so we can see under it from the wheelhouse.

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  Jean-Claude Noel says:

  What a beautiful sailboat. The lines are beautiful. It sits so well in the water. It seems to sail effortlessly. A feast for the eyes.

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  Ian Hendrie says:

  👍

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  Larry Cheek says:

  Would the designer please append an explanation here of how the foil mast rotates, both at the base and masthead where the shrouds and halyards attach? The form makes excellent sense aerodynamically, but I keep thinking that the engineering must be extremely problematic—or else production builders would all be doing it.

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    SCOTT SPRAGUE says:

    The mast rotates 90 degrees to each side, 180 degrees total. This is enabled by a mast fitting we designed and built that allows the rotation of the mast while the stays remain rigid. There is no fixed backstay, though what we would usually call the “lowers” angle back enough to provide support in addition to the running backstays each side. There are no conventional spreaders. It took a fair bit of thought to get that fitting figured out; it doesn’t show in the video.

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      Larry Cheek says:

      Thank you, Scott. If you’re going to be at WBF again this year, I’ll come by to look at it. I’m very intrigued. Congrats on your excellent design and engineering.

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      SCOTT SPRAGUE says:

      I should also explain that I stepped the mast on the top of the deadwood/ keel with a 7″ diameter ball bearing/thrust bearing on the mast step (visually similar to a “lazy Susan” style bearing race). The “bury” from the cabin top to the keel helped the stiffness of the mast as opposed to the deck stepped option. So, the foil shaped mast at the mainsail tapered and faired into a 7″ diameter round sectioned mast from the deck down to the keel. However, doing it again from scratch I would do as most everyone else with wing masts do, and use a deck stepped single ball, similar to a trailer hitch. That way there is no misalignment issue. Being a dynamic mast that is always self-flipping over at every tack or sheet adjustment, I suspect that some of the ball bearings are being loaded more than others (though I am not seeing any problem). The deck has a UHMW collar/bearing allowing rotation while holding it tightly in place which only experiences side loading. The deck stepped wing mast would need to be a stiffer section.

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  John Wujack says:

  I’m thrilled having Tumblehome close by my homeport of Poulsbo, WA. Several times per season, I sail down to take a look at this most interestingly shaped boat while always wondering what she looks like down below. Very special and beautifully done. Thanks for sharing. Regards, John

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    SCOTT SPRAGUE says:

    Thank you, John. I look forward to seeing you on the water.