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1 VOL 1 NUMBER 4 WWW.SKINNYHULL.COM Skinny Hull Canoe & kayak Sailing Magazine THE STORY OF SAILING CANOE P7 - PAGE 4

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Skinny Hull magazine is the global voice of canoe and kayak sailing.

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Page 1: Skinny Hull Vol 1 No. 4 April, 2012

1VOL 1 NUMBER 4WWW.SKINNYHULL.COM

Skinny HullCanoe & kayak Sailing Magazine

THE STORY OF SAILING CANOE P7 - PAGE 4

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http://issuu.com/skinnyhull/docs/introductory_ad_sizes_and_rates?mode=window&viewMode=doublePage

Skinny Hull covers the world of sailing canoes & kayaks, Chesapeake log canoes, proas and all sorts of skinny-hulled sailing boats. We’re published on the shores of the Gulf of Mexico in Dunedin, Florida.

Skinny Hull is the Global Voice of Canoe & Kayak Sailing

Editor & PublisherEdward C. Maurer

Contact: [email protected](727) 798-2366

A publication of Edward Maurer Consulting, LLC. Copyright 2012 All rights reserved.

Act ions, act iv i t ies, bu i ld ing, modification, travel, techniques, etc. seen within are examples of what others do and participate in and should only be carried out by qualified individuals. The outcome of your activities remain your own responsibility. Properly wear and use all safety equipment. If you’re afraid of the water, stay away from it.

Skinny HullCanoe & kayak Sailing Magazine

What’s Inside?STORY OF SAILING CANOE P7 .....................................................4WHAT BOAT TO BUILD NEXT ........................................................14THE BOY’S BOOK OF CANOEING .............................................18A CRUISING SAILING CANOE FOR THE 21ST CENTURY ........................25MADNESS IN THE BOATSHOP ........................................................26HOW I BUILT MY FIRST HULL OF TORTURED ELASTIC PLYWOOD ......31

WRITERS AND PHOTOGRAPHERS GUIDELINES ..................................36

https://www.paypal.com/us/cgi-bin/

MEET US IN SKINNY HULL’S FORUM

- The RuddeR - http://skinnyhull.com/forum

ADVERTISEIN SKINNY HULL

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On the cover: sailing canoe “P7” designed in 1933 by well known Polish boat designer Mieczyslaw

Plucinski.

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STORY OF SAILING CANOE P7By Robert Hoffman, Varsavia, Warszawa, Poland

The best-known and widespread Polish sailing canoe was “P7”, designed in 1933 by well known Polish boat designer Mieczyslaw Plucinski. In fact, it was not a canoe - due to the flat shape of the transom - but the proportions of the hull were more like a type of kayak.

With release its plans in 1934 by the Glowna Ksiegarnia Wojskowa (Main Military Books), P7 was quickly popularized and many of them were built before the beginning of the 2nd World War ; building continued after war’s end.

The original plans of P7 were probably lost or destroyed in 1944 along with most of the pre-war achievements of Plucinski. Fortunately, preserved in single copies of this book, and article brochures 10 kajakow typu “P” (10 Kayaks Type “P”) from which comes these scans of the drawings. Mieczyslaw Plucinski wrote that P7 was designed and built for his own use but was persuaded to publish its plans in the book. The plans are precisely plotted and described on 38 sheets, with some parts such as frames, stem and transom presented in 1:1 scale. In addition to the plans are photographs of the finished boat under sail, and a way to quickly

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transform it into a row boat with a rowing seat mounted on the centreboard case with oar locks on outriggers.

Already in 1934, the year the book in print, at least a few copies of P7 were built, as evidenced by these photos.

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I have a particular fondness for P7 for two reasons:

First, my father during the German occupation (1939-1945), had one of these boats nearly to his exclusive use. She was owned by his older friend who had other interests in that time. The boat was stationed on the Vistula river barge moored at the foot of the slope, over which stands the monastery of Camaldolese, in the Bielany part of Warsaw. As a teenager my father used every spare moment (and sometimes,

as he told himself he created them, because the monastery was a vocational school of building roads, which he attended, so the boat could easily flee to truancy) to the singlehanded sailing of P7 on the Vistula. The Germans didn’t care as long as he didn’t approach bridges and other strategic objects. My father told me other friends sailed a bigger boat

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named “Lorelei”, painted in German gothic style letters, that they sailed under bridges in the centre of Warsaw near bridges and German Yacht Clubs. Certainly it was not resonable and not common since it was strictly prohibited and extremly risky if caught by the Germans, but their desire to

sail was huge!The second

reason is that from 1966 to 1981 our family had a boat built in the 1950’s based on P7 with some modifications, but it was easy to recognize the features of the original - not just external, but also structural.

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Technical data of sailing canoe P7: Length Overall (L.O.A.) 5.00 m (my note: according to construction drawings 5.03 m) Length waterline (LWL) 4.73 m [15.5 feet] Greatest beam (B) 1.03 m [3.38 feet] Beam at the waterline (BWL) 0.91 m [2.98 feet] Draught of hull (T) 0.12 m [0.39 feet] Draught of hull with a centreboard 0,60 m [1.97 feet] Side height (H) 0.32 m [1 foot] Freeboard height (h) 0.20 m [.66 feet] Displacement (V) 180 kg [397 lbs] Weight circa 70 kg [154 lbs] Rigging: a) Cruising, gaff 7.5 sq m [81 sq ft] b) Racing, Bermudian 7.5 sq m (my note: in book no drawings of these sails)

I learned to sail in this boat, I experienced my first storm, and I had a great cruises. I will always remembered her with great fondness.

Thank you very much to my friend Marcin Bober who providing the historic prints. Unfortunately - from the time the paper was acidified and the destruction of construction drawings themselves are in a state that the execution of their scans, or photocopying, without having to undergo maintenance treatments are threatening to damage and irretrievable loss. Professional maintenance of prints is expensive, so still wait for their access to a wider audience.

Editor’s Note:My first impression of P7 was a modern design boat with

a lot of old world character. I want to build it. I see this as a real candidate for a stitch and glue build that any reasonably competent--and confident--person can build. The Supplement following on the next page, along with explanatory text and lines, should be adequate for what could end up as a fun project resulting in a skinny-hulled boat that will be enjoyed for a long time.

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Supplement:Mieczyslaw Plucinski repeatedly modified his design P7 – just in May

1939 he designed new version named Sailing Gig P7. The beam overall was increased to 1,20 m with more rake to the sides. Sails, bow, stern and centre board was modified also. Plans of this version available thanks to Norbert Patalas who has Plucinski’s achives. After the war, when Plucinski lived in Gdynia, the new version of P7 got higher sides for sea waves. In 1958 she was totally redesigned - establishing quite a new boat named P7-bis (L.O.A. = 4 m, B = 1,4 m, S = 7,5 sq m) which was popular also.

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WHAT BOAT TO BUILD NEXTPart 2 of a series by John [email protected]

As I mentioned in the last post, I started to do some work on the original linesplan for the late 19th century decked sailing canoe Isalo to explore making the arc bottomed hull suitable for the flat panels of stitch-and-glue construction. I began drawing by hand, but then I decided to put the lines on the computer and see what I could come up with. To do this, I used a hull design program called DelftShip, a development of an earlier program called Freeship (which is still available from SourceForge). Both programs are powerful, full-featured naval architecture packages, and both are free. Once you figure out how to use them for canoes, you could also design yourself an oil tanker, passenger ship or tug if you’re so inclined. A professional version of Delftship with more features is also available for €150, with the latest version slated for release in late February. These programs have a steep learning curve, no pun intended, but are well worth the investment of time.

One thing they’re particularly useful for is projects like Isalo, because with them you can import a scanned linesplan of unknown scale, such as you might find in a magazine, and, as long as you know a couple of the principle dimensions, draw new fair lines on top of the original. There’s a handy tutorial about how to do this, based on, of all things, Leo Friede’s legendary 16-30 sailing canoe Mermaid on the WoodenBoat Forum. If you use this tutorial, go through it with the DelftShip manual in front of you, because author Bruce Taylor leaves out a couple of important steps whose absence will drive you crazy until you also read the DelftShip tutorial on Reproducing An Existing Lines Plan, which you can download from the company’s web site.

The original Isalo circa 1892

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Even though I’m planning to add one or more chines, I thought I would start by getting Isalo‘s original arc-bottomed hull re-drawn in DelftShip. After a weekend’s worth of work, here’s what I’ve come up with:

This is the main Delftship window with all four views: perspective, profile, plan and body plan. Much as with regular lofting and fairing, you alternate between them, working iteratively on each one to gradually firm up and reconcile the lines. In each case, the starting point is the original linesplan in a background layer, on top of which you work with curves and the control mesh to shape the new lines.

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Andre Cloutier’s 16x30 at sailHere’s the profile with the three main lines defined: the centreline of the

hull [composed of bow, stern and bottom], the chine and the sheer.

And here’s the body plan, with the control curves [red] and stations [green]. Once you begin to develop the wireframe, you can add the other side of the hull and shade it to check on your progress.

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One of the most useful features for a project like this is that you can also run a developability check on the panels to see if they can be gotten out of plywood, which nominally doesn’t like to do compound curves, though you can torture it into shape to a certain extent. When you use that feature, the program adds red shading to show you areas that can’t be expanded into flat sheets.

DelftShip is telling me that the sections below the chine aren’t developable, which is not surprising since they’re still the original rounded arc bottom. The good news is that I seem gotten the topsides pretty straight, as it’s all green from sheer to chine. The next step is to go back to the body plan and make sure I’ve added enough curvature to the bottom to capture the volume of the original hull below the waterline. After that, I’ll ask DelftShip to calculate the hydrostatics to get some numbers against which I can compare my multichine versions as they’re developed.

Until next time. . .

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THE BOY’S BOOK OF CANOEINGCanoe Sailing, Chapter XIIElon Jessup, 1926

WHEN a Northwoodsman is ready to paddle across a lake and sees that he will have a favoring wind behind him, he sometimes reaches for his axe and cuts a small cedar before pushing off. This he places in the bow of the canoe. Presently, the green boughs towering above the gunwales become a target for the wind.

An Improvised Sailing Rig. -- Here you have canoe sailing in its most simple form. The tree serving as a sail of sorts augments one’s paddling. If you wish to dispense entirely with the task of paddling, you can devise a slightly more comprehensive rig from materials at hand by cutting a couple of spars and attaching to these a canvas camp tarp. The chief drawback to this improvised arrangement is that the mast may pull out and upset the canoe. In case you try this rig, special attention should be given to the mast’s security.

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The foregoing is about the nearest approach to real sailing that you ordinarily find in the North Woods. When starting upon a canoe trip in such sections, it is hardly worth while to include a sailing rig in your outfit. But there may be stretches in which the suggestions just given may be applied to advantage. In localities where you are unencumbered by equipment and canoeing is mostly a matter of just a few hours’ sport, sailing is certainly worthy of consideration: with the qualification that you know how to swim.

The Decked Sailing Canoe. -- The most highly specialized form of canoe sailing is found in the decked canoe, an individual type of craft which has been developed exclusively for sailing purposes. Ordinarily, it is an all-wood canoe of the same general lines as an open paddling canoe, sixteen feet long and about thirty inches wide. But it differs in various particulars. With the exception of a small cockpit amidships, it is entirely decked.

Among other distinctive features are a centerboard and a sliding seat. The centerboard extends about three feet below the bottom and the seat extends twice that distance beyond the boat’s side. The canoeist steers and trims his sails from this unusual seating position far out over the water. By means of a sliding arrangement he pulls himself toward or away from the side of the craft as the wind and dipping leeward rail dictate. His weight is needed far to windward in order to offset the great amount of sail the craft carries. There are two sails, these having a total area of perhaps one hundred square feet.

A man has to know a good bit about sailing in order to keep this speedy craft right side up. But even though it does upset, it readily keeps afloat and is easily righted. Sometimes a canoeist, when faced by a bad squall, intentionally upsets the craft, waiting for the squall to pass. The boat is provided with watertight compartments which make it unsinkable and it is self-bailing in that water runs out through the centerboard slot.

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Sailing the Open Paddling Canoe. -- Now, then, let us turn to the sailing possibilities of the ordinary open paddling canoe. The decked canoe just described might be likened to a racing yacht. So far as all around usefulness is concerned, the open canoe is a more practical proposition in that it may be used either for sailing or paddling as the spirit moves you.

Once you have the rig it is a matter of only about three minutes to turn the adaptable open canoe into a sailing craft and later the rig can be dismantled with equal ease. The only permanent additions required in the canoe are a special crossbar at gunwale level and a mast step below it -- these to support the mast.

The Single-Lateen Rig. -- Various types of rigging are possible. The single-lateen sail is the safest, easiest to handle, and most generally satisfactory. This is a triangular sail attached to two spars which are linked together at their meeting point, forward of the mast. The slanting upper spar swings from the top of the mast; the mast is short and stiff.

Only two lines are essential in this rig -- the halyard by which the sail is hoisted and the main sheet, fastened to the lower spar near its outer end. The size of the sail may range from forty to seventy square feet, depending partly upon the size of the canoe and partly upon one’s skill at sailing. The greater the sail area, the greater the chance of being upset.

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Ordinarily, a sail area of forty-five square feet is sufficient for a sixteen- or seventeen-foot canoe.

The keel of the average open canoe extends only about an inch below its bottom. This depth is insufficient to prevent the craft from making a considerable amount of leeway when you are sailing to windward. The most satisfactory method of minimizing this side drift is through the use of leeboards -- simple and effective substitutes for a centerboard.

Leeboards. -- Leeboards are a pair of wood blades, each about thirty inches long and ten inches wide screwed to either end of a detachable crossbar which straddles the canoe from gunwale to gunwale. These complete the canoe sailing outfit. A rudder is a convenience but not essential. One can steer with a paddle. It should be a strong paddle and fairly long.

Canoe sailing and ordinary boat sailing are identical in most essentials. The chief point of difference is the matter of balance. The boat sailor of experience in handling a sailing canoe for the first time should be guided accordingly. He is handling (relatively speaking) a featherweight craft that tips easily. As a rule, the floor is the safest sitting position from which to navigate. Perhaps one may climb to the windward rail in a freshening breeze, but he needs to be sure of himself.

Rules of Safety. -- The canoeist who has never sailed a boat should become familiar with the theory and practice of the knack of sailing and some of its fundamental rules of safety. There are two rules which have general application. The first of these is as follows:

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Head into the wind when you see trouble coming or something goes wrong, perhaps a sudden squall or jam in the rigging. The nautical term for this is “luffing.” When you luff, the sail flaps idly and you cease to make progress, but in nine times out of ten it will prevent serious trouble. Luffing is the great cure-all in navigating almost any kind of a boat.

The second fundamental rule of safety is the following:Opportunity for instant release of the sail when a sudden puff or change

in direction of the wind demands this. Inability to pay out the sail quickly is one of the chief causes of upsets. Therefore, the mainsheet should never under any circumstances be made fast to the canoe. It should be held in the hand.

A third rule of safety, not so generally applicable as the foregoing two, but certainly so in a heavy sea, is as follows:

Don’t sail squarely abeam of the wind. In other words, don’t have the length of the canoe at right angles to the wind so that you wallow between wave troughs. This position is sometimes a temporary necessity when you change your course.

That which makes a sailing canoe travel is a sail full of wind. The full breadth of the sail should be exposed to the wind although this means that the sail is at one time hanging far out over the water, while a few moments later it may be hauled in close to the side of the craft.

Sailing to Leeward. -- To sail in the same general direction that the wind is blowing is known as “sailing to leeward.” This is the most simple part of sailing. Even a piece of driftwood with a favoring wind behind it can travel from one side of a lake to the other. But, of course, the knack of sailing a canoe to leeward isn’t always so easy as that.

The waves show you the direction of the wind. When you are sailing to

leeward, the position of the sail and boom in relation to the wind’s direction should be at a right angle or nearly so. The boom, therefore, is reasonably parallel to the waves. When you sail with the wind directly behind you (“running free”), you release the main sheet until the boom is at a right angle to the length of the canoe.

When “running free” in this manner, one should keep a watchful eye for “jibing,” a trick usually caused by a puffy uncertain wind. When this happens, the boom suddenly sweeps from one side of the craft to the other. There is need for an extra amount of caution until the sail again meets

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steady pressure from behind. And at such times, a well-centered position on the floor of the canoe is highly desirable from the navigator’s standpoint

When the wind shifts or you change your course, it becomes necessary to haul in the mainsheet in order to keep the sail full. The amount that you

haul it in is dependent upon the force of the wind and the angle at which it strikes the side of the canoe. With practice one soon acquires the knack of alternately hauling in and paying out the mainsheet as the wind or your

course dictates. Keep the sail full of wind. But don’t keep it too full, for that’s risky.

Although a piece of driftwood can travel from one side of a lake to the other with the wind behind it, it can’t travel back again against the wind. A sailing craft can. That’s where skill comes in.

Beating to Windward. -- Sailing against the wind, the nautical term for which is “beating to windward,” is the reverse of sailing to leeward. In this case, the boom and sail are very nearly parallel to the direction of the wind. Of course, you don’t sail directly against the wind; that would be impossible. You compromise by taking a zigzag course consisting of a series of angles and a number of long tangents known as “tacks” connecting these angles.

Each angle is a turning point in your zigzag course, where you “come about.” That is, you reach the end of one tack and wish to turn and start off upon another. To do so, you steer the bow of the canoe head-on into the nose of the wind or, in other words, “luff.” The bow swings slowly around to the opposite direction from which it has recently been pointed; the sail, now on the other side of the craft, fills again and you are off on your next tack.

Successfully to sail a canoe to windward during these tacks, you should

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keep the bow of the craft nosed as much into the wind as possible and still have the sail full. When you nose too much into the wind, the sail begins to shiver and shake -- an indication that the wind pressure upon it has diminished. Therefore, you must “fall off”; one comes to learn how close to the wind one can sail and make good headway. This is the secret of beating to windward.

As in the case of sailing to leeward, one hauls in and pays out the mainsheet as various maneuverings demand. When pointing close into the wind you sail “close-hauled.” In other words, you haul in the mainsheet until the boom is almost parallel to the length of the canoe.

A word concerning the operation of leeboards. When you are sailing with the wind, there is no real need for the boards being in the water; in fact, they may even prove a slight hindrance to progress. Whenever they are not needed to prevent side drift, they can be swung upward in much the same manner that a centerboard is raised from the water. Similarly, they should be swung clear of the water if an obstruction is encountered.

It is in beating to windward that special attention must be given to the element of leeway. If the leeboards are not in the water (one, at least) you will drift sideways, crab-fashion at almost the same rate you go ahead.

The most important requirement of canoe sailing is the ability to swim. A cautious paddler may paddle half a lifetime without having an upset, but a canoe sailor, irrespective of how clever he may be, is pretty certain to go over sooner or later. A bathing suit is suggested as appropriate clothing. As regards various types of open canoes for sailing, the sponson canoe is by all odds the safest.

44sq foot sleeve lateen sail. Free rig plans. Stows flat for paddling

and storage. USD $322 plus shipping Contact: Marilyn Vogel Green Lane, PA 18054

[email protected]

American Canoe Association Sail for Sale

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BUFFLEHEADa CRuising sailing Canoe foR The 21sT CenTuRy

The Bufflehead design follows over twenty years of investment in monohull sailing kayaks and canoes for cruising; replicas and re-invention I’ve tried to avoid. Physics, and today’s materials and ideas about aero- and hydrodynamics I’ve tried to respect, while attempting to apply the lessons of the 19th and 20th century boats.

Bufflehead follows eight decked sailing canoes built on a proprietary hull—the best we could find at the time—Dave Yost’s Bell Starfire. Puffin and Meade Gougeon’s Serendipity were the first two, then the six Serendipity sisters, all with sheers re-cut for decks.

Bufflehead is 15 feet 5 inches by 33 inches. Her shape differs greatly but subtly from most 19th and 20th century designs by tilting to fast sailing under a broad range of conditions. Depending on how one chooses to build her, weight will likely be 40-60 pounds compared to the lightest Starfire hulled sailer at just under 40 pounds. Bufflehead’s cartop weight is 58 pounds, but she has a heavy, oyster resistant bottom. Displacement is 380 pounds, reasonable for an expedition boat considering freshwater needs in the tropics.

Bufflehead’s systems were developed further with the Serendipity series. Three rig styles have been used. Rudders are kick-up aluminum plates controlled by steering sticks. The leeboard pivoting system relies on a Jan Gougeon innovation. The seat design is effective for sailing and paddling, and adjusts to fit anyone.

For more information about plans for building your own Bufflehead,contact Hugh Horton at [email protected]

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MADNESS IN THE BOATSHOPAnd the Madness Continues....By John C. Harris, Chesapeake Light CraftWe discussed CLC’s proa, Madness in Vol 1, Nos. 2 & 3. This continues the series. Ed.

I should have known that building a 31-foot multihull in CLC’s shop would cause a stir. My first blog post about the boat, back in September, has attracted almost 9000 hits as of this writing. At the time, the proa’s nascent assembly was bundled off into our storage lot under tarps while the shop was busy with boatbuilding classes. We resumed work in November. And while I’ll not be retiring on sales of kits and plans for a 31-foot proa, the positive feedback is gratifying and has spurred Madness along. Here are some notes on construction so far.

The main hull was all in one piece, briefly, as a way to get the bulky parts out of the way for our December open house. But seeing the shell of the main hull in three dimensions was great fun.

The ugly external stringer visible at the chine is temporary. It helps align the side and bilge panels, and most importantly helps to fair the very long, gentle curve of the chine. Over a distance of 30 feet, 6mm plywood is really floppy, and needs assistance to take on a fair curve.

In these December photos (above and right), the side panels are missing their internal reinforcing stringers. There’s a cypress stringer that runs the full length of the side panel on the inside at mid-height, to eliminate “pumping” of the sides while moving fast through waves. Sheer clamps have been glued on, too, to which the deck will be fastened. Amidships, two big bulkheads mark the very beginnings of what will become the cockpit and cuddy cabin. Crossbeams will fasten to these substantial bulkheads.

CLC boatbuilder Carey is in the photo for scale.

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Like any stitch-and-glue boat, large or small, it has been possible to prefabricate almost every component in the boat. We cut the parts on the CNC machine, bring them up to the shop, and assemble them with “puzzle joints” on a long, temporary assembly table. We apply the fiberglass to inside faces of hull parts with the part laid out flat. Combined with the copious use of peel-ply, we’ve been able to finish the interior surfaces all of the way to 220-grit, rapidly and easily. All at a comfortable, horizontal, benchtop working height!

We’ll glue on the side panels once the rudder trunks are installed. Rudder trunks have to be installed before the sides go on; otherwise the internal attachment would have to be done with the boatbuilder suspended upside down by the ankles in the deep, narrow main hull. Rudder trunks, in turn, are awaiting completion of the rudders themselves. The top and bottom bearings in the trunks are molded to the finished shape of the rudders, for a secure fit in the trunk.

The rudders are a tricky bit of fabrication. They aren’t for the absolute first-time punter, but the average woodworker will get through it. The rudders have to be strong, very carefully shaped, and of course light. Mine are sitka spruce sheathed in fiberglass. The shaft is thick-walled stainless

The stems are flat above the waterline---for the moment. Structural polyurethane foam will be glued to those and shaped, then sheathed in ‘glass.

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tube. They are engineered to survive a high-speed grounding. If the grounding is on coral or granite, they’ll hold up about as well as a daggerboard or skeg rudder on a sailboat of similar weight and power. The rudders were the first Madness component we started on, back in May, to ensure rudder construction wasn’t rushed at the very end of the project. (This happened on my last proa, with memorable consequences out on the water.) Both rudders are rough-shaped at the moment, ready for final filling-and-fairing.

While we await assembly of the main hull, construction of the outrigger continues apace. Now, there’s a loose consensus among the multihull literati that the proper term for the outrigger is “ama,” and that’s the term I’ve used myself for twenty years. But even among yachtsmen, I mainly get blank stares when I refer to an “ama.” They understand when I talk

Mark, CLC boatbuilder, poses with one of the 6-foot tall rudders, assembled for final shaping. That’s a Schade Petrel kayak under way behind him.

Fiberglassing the 22-foot outrigger. More than one person has observed that, equipped with its OWN outrigger, this clean hull would make a remarkably good daysailing proa!

Fillets and tape on the interior of the outrigger. The compartment between the structural bulkheads will contain a combination of water ballast tanks and line & fender stowage.

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about the “outrigger.” So I’ve decided to start calling it the “outrigger” when I speak of it publicly, and “ama” when talking to the multihull elite. (“Aka,” by the way, is the official term for “crossbeam,” unless you’re in the OC-1 world, in which case it’s “iaku.” I’m going to start calling them “crossbeams” except in selected company.)

Madness’s outrigger is 22 feet long and 21-1/2” wide (6.7m x 0.55m). Stitched up and fiberglassed, it sure looks fast. Very fine-ended. I was somewhat comforted to find proa Jedi-master Russell Brown almost as frustrated with outrigger design as I am. The outrigger is alternately skimming the water, then being driven bodily through a wave crest. Make it too fat, and you get lots of drag. Too small or too fine, and it acts like a submarine. I sure got it wrong on the first iteration of Mbuli; I will never forget watching its

outrigger torpedoing along at 10 knots---30 inches UNDER the surface of crystal-clear Tampa Bay. This may sound like fun, but the crew felt like they were waist-deep in Class III whitewater. Gets old. We’ll find out if I got it right. The good thing is that it only took 3 or 4 days to knock the outrigger together, so I won’t feel any reluctance to refine the shape.

While CLC boatbuilder Carey grapples with Madness in the shop, I’ve been working the phones tracking down a mast and sails. No luck so far on a mast. I’ve decided I can’t afford a carbon fiber mast, so I’m in the hunt for an aluminum mast section from a Hobie 21, Tornado, Nacra 20, or similar. Please give me a shout if you have a line on a good light mast section over 31 feet/9.5m.

Russell Brown referred me to Sandy Goodall’s outfit for sails, and I’ve placed the order for a main, two jibs, and an asymmetrical chute. I’ve decided to have them made in Vectran, which is a performance fabric that falls somewhere between good old Dacron and more exotic (and less practical) mylar laminates. The total for the new rags came to $5600, quite a lot more than I have in the entire rest of the boat so far.

Fillets and tape on the interior of the outrigger. The compartment between the structural bulkheads will contain a combination of water ballast tanks and line & fender stowage.

An early drawing of Madness, with a simpler mainsail.

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In Dacron, with a simpler pattern, they’d cost substantially less. A huge variety of stock used sails would fit, too.

I have a fixation on sail quality, dating to my teenage years. I got slaughtered on the race course because my racing dinghy had ancient hand-me-down sails. When I finally acquired a new set of sails, the improvement was so stark that I’ve never been able to abide bad sails since. Sails are the engine, the entire motive force of your sailboat, the whole point of the exercise.

Coming up next issue, more progress photos and a study of what Madness has cost to build so far.

The final sailplan. The front view shows how the mast is stepped to windward. This innovation, which belongs to Russell Brown, means that the mast is strongly supported in an “aback” situation by shrouds led out to the stems (clear of the boom). The mast will be held in column with diamond stays.

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HOW I BUILT MY FIRST HULL OF TORTURED ELASTIC PLYWOOD IS SHE SKINNY ENOUGH? By Jacek Sterna, Warsaw, Poland

Three years ago I built a small Pacific Proa with a crab claw sail. I used the previously built tortured birch plywood canoe and added an outrigger, spars, sail (tarpaulin), ropes, and a leeboard. Once completed, I was unsatisfied with the finished product. The hull was undecked with gunwales that measured 30cm high, L360cm and B70cm. While this hull would be suitable for one paddling on a river, I was hoping to build something to sail on a lake. When the wind reached around 3 B (Beaufort Scale 3: winds 7-10

knots. Ed.) I found it was hard work. I used one hand to bail water the other for the sheet. I desperately needed to grow a third hand to steer when sailing downwind. The crab claw with curved spars was built using a design conceived by Janusz Ostrowski, the leeboard hanging on the rope was my idea, and both worked perfectly. It was obvious to me however, that I needed a longer, decked hull. I deduced building a new hull would surely be easier than growing a third hand.

A few years ago, Krzys Mnich designed a

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“dumpling-like” hull for a large seagoing Proa. (http://www.port21.pl/2008/05/proa-z-inspiracji/ ) Let’s take a moment to appreciate the quiddity, in my language “pierogue” is the same as “piroga”, but “pierogi”or “pirogi” means dumplings. This hull should be formed using elastic plywood, as a dumpling is formed using a rectangular sheet of dough. Of course the plywood for the hull would be considerably elongated. Unfortunately, nobody built such a hull.

As I researched this “dumpling-like hull” I searched “elastic plywood” on Google. Do the same, and you will discover a light and flexible substance, perfect for rolling along the grains of the outer layers of wood. Unsurprisingly, the cost of this material is more expensive than “normal” plywood. For a 16 footer, you will need (fortunately) only two sheets of 5mm elastic plywood, one 4mm sheet of birch plywood, a half a sheet of 10mm birch, and finally some spare wood.

Initially, I had high hopes this “elasticity’ would work to my advantage, and make for a very quick and easy building outside. Especially as most of the women in our lives would likely protest the sounds, smells, and mess this construction would create. Certainly, the woman in my life!

Moving forward using this new found plywood, I decided to use a more conventionally (flat deck) shaped hull, as opposed to the dumpling shape. I purchased two sheets of elastic plywood made of fuma (fromager, or Ceiba

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pentandra, or kapok tree) wood. These sheets were wrapped in a piece of tarpaulin, as it was a rainy day. They were transported easily on the roof of my car to the garage where I stored the plywood, after impregnation with fungicide.

I built the hull on the lawn of a cottage on Liwiec, a small river northeast of Warsaw where my wife and I spent our summers. All told, the hull took 15 working days to construct in July 2010. The hull was built in two halves to be easily car-topped.

First, I used polyurethane glue to cement the first layer of gunwales to make the edges of the plywood stronger. Then, I made straight cuts on both sheets of elastic plywood as pictured. The four small triangles were discarded. I then cut four frames of 10mm birch plywood and two stems of alder wood with a jigsaw. (Below) The frames and stems were wrapped onto the plywood sheet and glued together. The excess plywood, indicated by a red arrow (see image next page), was cut off in order to create a straight line on the bottom (not a concave one). The hull was made in two sections--fore and aft-

-that would be joined to create a single hull. The “end frame” of each hull half was covered with 4mm birch plywood after glassing the outer side of the hull to close the compartment under the floor of the cockpit. The piece of plywood between the end of the

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stem and the bottom was rounded by sander. This part was very difficult to stitch and glue because of its tendency to deviate. Eventually, I squeezed this troublesome part of plywood between two pieces of an old plank in clamps. In my opinion, it would be better to make the stem as long as possible, reaching just to the bottom of the boat. Inside the boat, the entire seam, from the bottom up

to the stem, was sealed with putty. I opted to use whole grain wheat flour for the putty because the color is similar to that of the fuma wood.

The stems were too short and another problem arose; the frames in the middle of the boat’s halves didn’t match the plywood on the bottom. Between the bottom and the end of the frame was a 3cm slit. I glued pieces of 10mm plywood to the frames to cover this space and then applied a large amount of putty. This frame shouldn’t be round at the bottom, but rather an ogive.

The rest of the building was fairly uneventful and conventional. On the last day of building I made forth varnishing on the glassed hull.

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YOU, TOO CAN BE PART OF SKINNY HULL, HERE’S HOW!

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