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Samwise - Part 3

Some fairly dramatic changes since Samwise Part 2 (Part 1 is here). The biggest change is that Sam is now a balls out Atlantic proa - rig placed in the windward hull. No faux Pacific, "weight to windward" sham, an Atlantic proa is Sam I am. Larger pics after the jump.

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Canoes of Oceania

Harmen Hielkema has joined the blogosphere at Canoes of Oceania. Harmen designs and builds proas in New Zealand with an artistic eye and an appreciation for prior native art. From his blog:

Every culture with very few exceptions, somewhere in its past has some connection with the sea and a technology for moving or sailing on it. The sailboat was the first machine to give men freedom of motion without harnessing muscle power. Few of us any longer recognize that the sailboat was truly the first instrument which freed us from bondage to the land ... the waka ama, the first sailboat that could move up wind. This invention made previously inaccessible areas of the world accessible to man, ... Neither do we recall, unless our attention is drawn to it that the sailboat was the first machine to achieve powered motion without rotating parts. Bernard Smith, The 40 Knot Sailboat, Grosset & Dunlap, New York, 1963.

The Cat Came Back

Via the Boat Design Forum: Tornado sailors, Steve Lohmayer and Jamie Livingston, going under the team name of Lumpy and Bumpy, have won the annual Watertribe Everglades Challenge in a record time of just under 36 hours.

The Everglades Challenge is a 300+ mile adventure racing event that runs from Tampa Bay's Ft. DeSoto beach to Key Largo. The previous record for the event was set last year with a time of two days, 8 hours, 56 minutes by a 22 foot, double-handed skiff.

Lohmayer and Livingston passed fellow multihuller, Randy Smyth, about two thirds of the way down the course, when his trimaran suffered an unknown breakage, forcing Smyth to retire. Randy then found transportation to the finish line to greet the Tornado team upon their victorious arrival.

It's nice to see a multihull take the cup of this spectacularly challenging race. The Tornado class catamaran is (by multihull standards) an ancient design, from the drawing board of Rod MacAlpine-Downie Jr. 20' x 10' x 233 sq. ft. SA, the boat is one of those rare creations that somehow seems greater than the sum of its parts. A perennial Olympic class, the cat was recently eliminated - causing great dismay among multihull fans.

Samwise - Part 2

I fleshed out a few scale drawings of Samwise last week. In keeping with the minimalist theme, I'm doing the minimum of calculations. As you can see, proportions have altered a bit - but form follows function. The goal was to make the hull sides from straight ripped ply - 2' wide - easy as pie. The straight ply goal meant the crossbeams buried in the hulls had to go, so now they're lashed or bolted to the deck in beach cat style. The cabin has comfortable sitting/laying about headroom, 2' beam on the bottom. I'm debating whether I need a solid cabin or not. I could see small dodgers fore and aft, and making him into an open sailing canoe.

Still no rudders, as you can see. I'm quite certain the boat will self-steer as if on rails on most courses, and it would be fun to steer the boat by sail trim alone, and no rudders would save a lot of building time and trouble, but still... rudders are nice.

My enthusiasm for the lug rig has not abated. Masts are only 17' long! Read more about standing lugs in this Duckworks article by Michael Storer.


LOA: 24'
Length lee hull: 24'
Length windward hull: 20'

BOA: 12'
Beam lee hull: 1'-8"
Beam windward hull: 2'-8"
Interior headroom: 3'-6"

SA: 220 sq. ft.
Rig Height: 22'-8"

Crab Claw Tests

These are qualitative studies of slender foils and leading edge vortices for sailing craft. The results of these experiments, suffering from improvised input and variable conditions were good enough to inspire further work but produced more questions than answers.

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Samwise - There and Back Again

Samwise is a minimalist cruising proa, which is really the only kind of proa there should be, IMHO. The only thing not minimal is the performance - the proa’s raison d'etre. The basic idea is reliable and cozy camp cruising in the Pacific NW - where the water is generally frigid and the air is generally tolerable.

Sam’s godfathers include Matt Layden's Paradox and Rob Denney's Harry, while a host of uncles include Phil Bolger, Peter Spronk, Dick Newick and Ralph Munroe. He (all proas are masculine) features simple plywood construction, an enclosed sailing cockpit, plenty of deck space, endless conversations at the dock, and the ability to go there and back again.



The crew helms from an enclosed sailing cabin - which is a nice feature in the Pacific NW and its nearly iceberg laden waters. Laugh at the freezing spray as you drive like an arrow to windward! Mock the waves as they surge impotently against your plexiglass shielding! Unlike tacking craft, proa crew have no need to make the treacherous trek to the other side with every tack. You are always on the good side of a proa.

In the unlikely event of pleasant sailing weather, you can slide open the hatches, or sit atop the flat cabin top, or even sprawl out on the trampoline, catching the sun. The tramp will also make a fine place to pitch a tent for overnighting - if a real double berth is required.

The leeward hull is the load bearer, so it stretches out to 24' of lean, wake-cutting form. The windward hull is the ballast, which makes do with 18' of LWL. Skilled sailors will fly the windward hull at every opportunity. Being flat-bottomed in sharpie style, the hope is that it will plane if given half the chance.

The free-standing schooner rig makes for a criminally low center of effort, while the standing lugs create a powerful yet balanced, easily handled sail that requires no purchase on the sheets - which comes in handy during a shunt. The forward lug is rigged with the mast to windward (its most aerodynamically advantageous position) while the aft lug is set opposite, which moves the combined CE well forward (a desirable thing on a proa).

Leeway is prevented by a central, pivoting leeboard mounted on the leeward hull, and steerage is provided by fore and aft "dagger" rudders. The hope is that in the unfortunate event of a grounding, the deep leeboard will hit first, pivoting gently out of harms way as it stops the boat, whilst leaving the delicate rudder intact. As usual with proa designs, the rudders are sketchy... at best. From model testing, I found a schooner rigged proa such as this will balance and self-steer on most courses by sail trim alone - Sam, by nature, is a virtuous course keeper. Be that as it may, a real cruising boat needs a real rudder. Suggestions are welcome.

The proa's beam is retracted to trailer width via telescoping aluminum beams (as an option, Jim Shanahan has proposed an ingenious hinging mechanism).

Note: This sketch is a cartoon only. No plans are available.

Sailing Over Melting Ice

Something about this project has captured my imagination - Sébastien Roubinet is attempting to sail the Northwest Passage (Alaska to Greenland) this summer - yea, SAIL it! Thus far, only nuclear subs and diesel-powered ice-breakers have managed the fabled voyage (a voyage that inspired many an explorer, including Captain Cook's Third Voyage (thanks to Peter for the correction), who met his bloody end in Hawaii - "stoned" by the irate islanders as a false god...) but thanks to global warming, Roubinet thinks it might now be possible to navigate the passage via sail!

His ingenious vessel is half sailing catamaran, half ice yacht, and somehow it seems appropriate to see Captain Cook's dream realized by an artifact from the culture that played such a big part in his life, and death.

QueeQueg 18

Indian summer is officially over around here, and thoughts turn to winter projects in the workshop. I've worked up a little trimaran design, inspired by Solway Dory's Osprey and Chris Ostlind's XCR.

It's an 18' stitch and glue plywood, 5 panel hull, with tortured ply amas and aluminum akas. Hull beam is 30". sail area: 118 sq. ft. a high aspect leeboard would be included (not shown). It would be fun to day sail, and might make a good little camp cruiser.

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FreeShip Walap

I've found a way to force the freeware boat design softwareFreeship 2.6 to do proas, it may interest proafile readers.

The problem is that such programs assume that the port and starboard sides are mirror images of each other, so you can build a catamaran or a trimaran, but not a proa. Then I remembered that proas *are* symmetrical, only the axis of symmetry is turned 90 degrees.

The trick is simple: begin with the default design, and set the measures to say, 6 meters WIDE and 0.5 meter LONG. the hull will look weird at first, but once you move the control points around, it becomes pretty normal.

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FatCat21

Just a few months back, our Proafile host, Michael Schacht, introduced a set of concept illustrations for a very nice, 23' Hawaiian flavored catamaran called, Manu Kai.

Michael's vision was at once elegant in the manner in which it honored traditionally styled Hawaiian sailing vessels and it provided a set of unique solutions for how to blend the traditional with the modern in boat design.

Below the text of the article in the section for comments was a note from the author about the difficulties of designing this type of hull for a plywood build style. Since I design a lot of boats for stitch and glue plywood construction, I was immediately curious as to just how far down the path of the Manu Kai I could actually go with a possible design from that material/technique.

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