NOTE: Version 4.0 May 12, 2011 -- Added step 7 about a brief trimaran conversion for the Everglades Challenge. I talk more about sailing (and other things) at my blog, Tristram Shandy in the 21st Century, www.tristramshandy21st.blogspot.com --wt
Foreword According to the philosophy of "one boat for each day of the week," I built my Tuesday boat. The Monday boat was described in my instructable, Make Life Better with a Sailboat in a Closet. This Tuesday boat reflects some lessons learned from the Monday boat, some changed situations (for context always has a finger in the things we build), as well as the usual misguided notions that exist to help us set benchmarks for all human values.
What it is This boat is a tacking outrigger sailing canoe. It is a 3-board canoe, which means, in Western boat-building tradition, the main hull (vaka, in Pacific boat-building tradition) is a sharpie-style hull. However, the outrigger float (ama), is a two-board hull (Wharram style; more on that later). The sailing rig is a Western cat-ketch made from standing lugsails.
Youtube: See it in action here: http://www.youtube.com/watch?v=1L4J5EKSwEc This is the better of the videos so far, though a few more are posted under 'wadetarzia'
Materials: 1/4 inch CDX plywood, common pine for stringers, laminated pine shelving/desktop materials for boards, oak and Douglas fir for load-bearing struts, Douglas fir flooring planks laminated for akas/cross-beams, 6 oz. glass cloth, System Three epoxy, a few bronze ringnails, some stainless steel hardware, a few commercial blocks and cam-cleats, and low-stretch synthetic line for halyards, sheets, and downhauls.
Vaka/main hull: sharpie style, chine and epoxy construction, 16 feet length-overall, ~4 incnes rocker, 8 inch waterline at center with one person aboard, 24 inches main hull beam including gunwales, 14 inches beam at bottom, 23 inches depth of hull at center, ~19 inches depth at ends. Main hull weight about 160 pounds (glass and epoxy over plywood, double layer on outside bottom, single layer on inside bottom up to waterline. Open hull with partial decks and foam flotation.
Ama/outrigger float-hull: 14 feet length overall, 14 inches beam at center, 14 inches depth at center, strong rocker, V-hull style. Decked and watertight with screw-hatch access/ventilation. Weight about 70 pounds. Displacement: about 270 pounds.
Akas/crossbeams: Laminated from 4 strips of DF tongue-and-groove flooring planks (tongues & grooves adzed down), tapering to three strips toward ama-end, ~7 feet long (should be 8 feet but that's what I can scrape through my garage door). Weight about 15 pounds each.
Assembly: The parts are lashed together with 3/8 poly line (1/4 would be OK but use good quality marine low-stretch line) and tied off on plastic cleats. I use half-inch oak locating pins to lock the relationships of the aka to the main hull, but the whole lashed boat is still quite flexible, which is good for an outrigger canoe. Total beam is 7 feet.
Not so Right, Not so Misguided So you are wondering how this canoe represents a misguided notion? I started building it from cheap materials (CDX plywood and Home Despot lumber) because I intended it to be practice for the larger outrigger I wanted to build and build properly. Instead, each hour on the job, I invested more time, and more thought, and by the time I was done, I had so much time and money invested that it had transformed into THE BOAT. His name is Short Dragon.
Lessons are to be learned here, so do what you can. Meanwhile, I will tell you how I made the boat.
And More! Well, not yet. A few more things: Short Dragon has really pleased me. He is a good performer. If you are smarter than I am, you can build a better one easily by using better materials and having better skills. You can build it lighter by using fewer stringers, less epoxy and glass, etc. This boat weighs in fully rigged at around 280 pounds. But no matter. My economy car tows it just fine, in 5-10 knots of wind (reported from local airport weather probes, not known at sea-surface) he will cruise along at 5 to 7 knots. I have often hit 10 knots, sometimes 12 knots, and in one blaze of glory hit 14 knots, although we were probably "pushing the envelope" (blah, blah) near disaster.
Sailing not Paddling (Mostly) He would not be the best paddling craft, of course, with his boxy hull and heavy outrigger, but often I have had to paddle home after the dusk wind dropped me a mile or two from the ramp. In flat water you can paddle at 3 knots fairly easily for an hour (and I am not a paddling athlete).
A Main Point But my main point is, you would enjoy such a boat, I think. In medium air it will provide some fun, in light air it can take a passenger, but I recommend it as a solo boat unless you deck over the canoe hull almost completely, watertight). In light air.... you yourself can recall various bumpersticker proverbs concerning " is better than a good day at work..."
No Plans, Sorry As with my Monday boat, this boat had no plans nor was it "designed" except for some rough sketches and rough cardboard model making. I went by some commonsense, some constraints dictated by physics, and by what I thought looked right (having looked at a lot of sailing craft over the years). Some experience with the first proa, and many conversations with knowing and kindly people on internet boating groups helped out.
A small boat ought to be well designed, I agree, but other factors have powerful influences on the way a small boat behaves -- for example, where you sit, six inches here, six inches there, will alter trim and forces on the hull enough to change handling characteristicsw. By all means, do great design work, but if you don't have the skills, don't let that prevent you from trying.
But let's grind some French Roast, brew a pot, and have a look.
Step 1: Beautiful Models
But not here. I did some sketches, roughed out a paper model, then cut and scarfed plywood sheets into two 2 feet by 16 feet sheets (topsides). I cut the stem and stern rake angles (a foot back from edge looked right) and then stared and stared before drawing rocker curve (the curve upward from the bottom -- bottom center in this hull -- toward the ends to set the hull depth and its location = center of buoyancy = helps the boat turn and has other interesting hydrodynamic implications).
Step 1 (Photo 1)-- Mock-up one inch to the foot scale model of the topsides (2x16 inches) out of cardboard, paper, or thin modeling wood.
Step 2 (Photo 2) -- Cut the stem and stern rakes after brainstorming them. These rake angles affect aesthetics, the buoyancy of the ends, how the ends interact with wave shapes (a surfing canoe often rakes the stern to match the typical wave shape it is embedded in so that the stern does not dig in and slow the rate at which you can turn the boat to avoid broaching), and waterline length when boat is heeled (for raked ends, it increases when a boat heels, but this is less of an effect for an outrigger cane than it is for a constantly heeled monohull sailboat; increased waterline increases hull speed).
I built a symmetrical hull to let me convert the boat into a shunting proa (check out Proafile Magazine on-line or Wikipedia "proa" to see good explanations about proas). if you are building a dedicated tacking boat, you can play with changes in hull shape to better suit your sailing regime. But now I am too deep into the theory of nautical design, where I cannot be your expert guide.
Step 3 (Photo 3) -- Draw the rocker line. Think really, really hard about what the rocker curve should be. Read books about it. Talk to people. Remember, rocker is pretty much permanent. You can change some things after a boat is mostly done (if you must...), but rocker would be the one you cannot change without sawing the bottom off the hull.
I wanted about 4 inches of rocker because it seemed good. More rocker = more load carrying ability (more buoyancy volume), easier turning, and slower speed (in some cases); less rocker means less load carrying,better tracking, harder turning, more potential speed (in some cases). But rocker curve is more complex than I am making it seem here. I used a tiny batten to draw the curve, and (obviously!) a full sized one for the full sized sheets.
Step 4 (Photo 4) -- Clamp the sheets together (both for model and full sized pieces) to double-check symmetry. The pieces should match, in other words. Trim as needed.
4A -- For the full sized topsides, now is the time to epoxy in the gunwales, stringers (stiffening longitudinals (but see the next step for more on this), and the chine log (the strip of wood inside the bottom of the topsides onto which the bottom of the hull will be epoxied). Any plywood-boat building book or essay will tell you about such things.
Step 5 (Photo 5) -- Attach the ends to form the basic hull shape. (a) Tape the model ends together (drill small holes and wire the full sized topsides; the topsides have additional requirements: gunwales, stringers, chine logs, and stem/stern pieces, all epoxied to the inner sides except for the gunwales -- see next step).
(b) Cut spreader sticks (easy) or bulkheads (harder) to design in the profile of the hull. Wedge them in and move them around to set up the maximum beam (at both top and bottom of boat) and the curve of the profile. I planned on a trapezoidal sharpie hull and used sticks.
(c) Eyeball the hull from all angles and move the sticks a little to achieve fair curves. Eyeball the hull a lot because you can still change its design easily at this point, but not so easily after the next step.
Step 6 (Photo 6) -- When you are happy, you glue in your bulkheads or cross-pieces.
Step 7 -- Measure, trace, cut, and attach bottom. (a) You flip the hull, (b) measure the stem to stern lengfth on the bottom, being sure to follow the rocker curve, (c) scraf plyuwood for the bottom, (d) lay on the sheet for the bottom and weight down, (e) trace the bottom shape on it, (f) cut out the bottom, (g) use thickened epoxy to glue the bottom to the hull, and (h) trim the edges of the bottom flush with the topsides; later you will round off the edge and overlap fiberglass to protect exposed plywood edges.
Step 2: Building the Real Canoe Hull (Vaka)
The main idea here is that what you did to your model, you will do to your plywood sheets. If your model was large and precise, you can expand your measurements from the model to the plywood. The difference is, you have to scarf the 4x8 foot plywood into 4x16 foot plywood. Better, cut the sheets into 2x8 pieces for easier management, and scarf (I used butt-strap method) the pieces into two 2x16 foot sheets.
You will eventually also need a ~14 foot long by ~14 inch wide piece for the bottom of the canoe hull, but do NOT make this piece until you have settled on the rake of the stem and stern and then mocked-up the topsides into the basic hull shape. When you are happy with the hull shape, then you can measure for the bottom piece. So here are the basic steps:
Basic Steps for the REAL Hull:
But you have some some options about where you can place the stringers and how many stringers you use. Because the waterline of the bow is important, and because an outrigger canoe can attain fairly high speeds making submerged objects especially dangerous, I recommend placing a stringer at about waterline level: for this boat about eight inches above the bottom of the topsides. You might want to place a stringer at at the height at which you want to your seats, or a deck if you plan to sleep on the canoe. I placed these stringers about seven inches below the gunwales, which left me about 17 inches of width where my hips would go were I to lay sleeping bag out at that level. The stringers provide more hull strength and shape holding ability, but they do add weight. Your decision.
Photo 1 -- Topsides laced at ends and sticked out to set up the hull specifications. All stringers and chine already glued in.
Once the spreader sticks have their proper lengths to hold the hull to the proper shape, you will want to devise your permanent method for spreading the hull topsides apart. If you intend on dividing the boat into watertight compartments, now is the time to cutout cardboard blanks to design and install plywood bulkheads. If you choose a simple open hull, you can epoxy in your seats as structural members.
Photo 2 and 3 -- Interior of hull showing placement of ribs, chine log, waterline stringer (for hull strength), seat level stringer (or interior deck if and when the hull is decked over for safety in rough water), and the mast steps and partners at bow (#2) and stern (#3).
Photo 4 -- permanent thwart/cross-piece, provides hull stiffening and a heavy weather mast location for a tiny sail. The groove shown is to drain water off the stringer while the hull is open-hull style.
Photo 5 -- The central seat being fitted. Under this seat (hinged with line) will be a large block of flotation foam (lashed down) with room left for anchor and rode.
The placement of the sails requires some thought. You want the center of effort of the combined sails to allow a little weather helm. I eye-balled the hull, drew sketches of the hull and then cut out scaled shapes of the sails and moved them around the hull sketch to intuit where the forces would be going. This worked out pretty well. [WADE, MEASURE WHERE THE STEPS AND PARTNERS WENT AND INSERT HERE. READER, IF I DO NOT DO THIS BY THE END OF JANAURY 2010, PLEASE REMIND ME IN COMMENT. THANKS.]
Step 12-- Prepare for lashings: Drill the holes and install doubler pads in the inside of the hull (to give the wood extra support where the lashings will be straining the material) where you plan the lashings to pass through the hull. I used three-quarter inch pine blocks to back up the lashing holes. All holes that will feel lashing line should be well sanded with well-radiused corners to avoid fraying the rope. I always coat the holes with epoxy, and sometimes with epoxy graphite mixture.
Photo 6 and 7 -- The hull being glassed and the finished hull awaiting paint. A sharpie hull can be glassed easily after construction, but some builders recommend glassing the sheets before assembly. Keeping plywood perfectly flat helps you stop VERY frustrating epoxy runs that harden. I had no problems doing the outside like this, though. The inside dripped; I didn't much care.
Photo 8 -- The deck pieces go over bow and stern and keep out most waves that come over. A serious sea-boat should be decked over watertight (use commercial 6 or 8 inch screw-in access ports to stow gear and ventilate boat once home) except for an aft seat and foot-well.
Photo 9 -- The bow and stern bottoms got extra heavy strips of glass (17 oz!) and oak strips to take the brunt of abrasion suffered during beaching and moving boat on/off trailer. The stem and stern also got a strip of oak, epoxied on and then planed down to the hull width there (you see it before planing to width). The bottom of the the boat has two layers of 6 oz glass cloth and a final coating of epoxy-graphite. These durability features add much weight, of course. Pick your poison.
Step 13 -- Measure and build the decks to go over ~3 feet of the bow and stern. I glassed the 1/4 inch plywood, but that was probably overkill (and more weight). Do NOT epoxy these decks down because you will want to take them off when you inevitably modify the boat.
Step 14-- Prime and paint the hull. For this boat I used exterior latex semigloss. It lasts pretty well but not as well as marine quality oil paints.
Step 3: Build the Ama
The main design criteria for the ama is its buoyancy. How much load do you want it to take? This is a tacking outrigger, so the ama-to-leeward tack will press the ama down into the water. If the rig is tall and powerful and the wind is great, the ama could "trip" the boat into the dreaded "diagonal capsize." I am scared shitless of this event, so I have worked to avoid it. A well designed ama with enough volume helps.
Unfortunately the ease of construction of a plywood V-hull ama does not let you design in displacement far forward where it helps most in resisting diagonal capsize. As Tim Anderson says, "Everything affects everything else." Every design has a trade-off. Pick your trade-offs with full knowledge, and carry on.
I built the ama in V-hull style, like a Wharram catamaran (photo 1). It is the simplest way to get an outrigger hull by the way. If the vaka is a 3-board hull, the ama is a 2-board hull. But since you have to deck it over watertight, it ends up being 3-boardish. In any event, build the ama as you did the vaka, starting with a model. The basic ama will go together swiftly because you merely stitch it along the bottom, spread it out and adjust, and glue in the spreader sticks/bulkheads. I added gunwales made of 1/4 inch oak molding.
I stuffed much of the ama with Dow foam blocks for emergency flotation. I glued in rib-like wooden strips so that plenty of air spaces between inner hull and foam would remain to allow air circulation to dry out the insides (Photo 2). Even if your watertight deck and screw-in hatch are, er, tight, you might get condensation in there. Also, I installed glass strips to hold foam blocks off the bottom for the same reasons.
Step 1 -- As you did with the vaka, you will scarf two 1/4 inch plywood sheets 14 feet long and 16 inches wide. Then cut them to the shape you decided on. Match, clamp, and trim the pieces into mirrror images.
Step 1 A -- You can install the inner "gunwales" on which the decking will be screwed down; they are set down tot he thickness of the plywood decks: 1/4 inch. I installed these after the basic hull-shape was created. Not sure what method is best -- probably gluing in the stringers/gunwales first is best. I also added an outer gunwale of 1/4 inch oak molding. The inner strip will have to be planed level with each other later (like the chine logs of the canoe hull/vaka).
Step 2 -- Drill tiny holes for the copper wire about two inches apart and 1/2 inch back from the ede (what will be the keel and stem/stern ends).
Step 3 -- Stitch the pieces with wire, keeping wire loose enough to let the edges seat against each other on their inner corners.
Step 4 -- Temporarily spread-out the ama hull with sticks to achieve your desired planform and fair curves. State at the hull a lot, as usual. Tigthen the wires to hold the keel together firmly. Attach spreader sticks with screws when the shape is settled.
Step 5 -- Glue the keel and stem/stern with thickened epoxy (I used System Three Silvertip, which hardened well but resisted being squirted fromt he giant syringes I was using).
Step 6 -- After the keel epoxy is cured, install your permament bulkheads. You can see from the photo that I went wild at this stage. You probably do not need so many. I used available pieces from pine I had around. No reason why you could not cut them from plywood.
Step 7 -- The ama becomes more complicated as you add the upright sticks to which the akas (crossbeams) will attach. Use beefy sticks; the ama struts must NOT EVER BREAK. I used ~1.5 inch square Douglas fir.
The upright struts are glued with generous epoxy and epoxy fillets to the plywood sides, and strengthened with diagonal struts. Leave the uprights longer than you imagine needing, because when you do the first canoe-in-the-water test, you will be marking the unfinished struts to set the relationship between the canoe hull and the outrigger float hull; they should be rather level in the water with your typical crew load aboard, but don't be obsessive -- the trim of an outrigger sailing canoe will be constantly changing. When the height is marked, you can finish the struts with a crosspiece as I did. However, ama attachment methods are legion. Have a look at the ways other people do it. In particular, buy Gary Dierking's book, Building Outrigger Sailing Canoes, or go to his website.
Photo 6 and 7 -- The struts that will attach to the crossbeams/akas. Use fir or oak. Make them long so that you can cut them down to adjust attachment height. Glue and screw everything; this area takes much strain and MUST NOT FAIL.
Step 8 (photo 8 and 9) -- Build the deck pieces. I strengthened the large, wide center deck with glass and beams underneath (which touch a bulkhead glue inside) because I planned on standing and sitting here while using the ama to climb back aboard the canoe after a swim. A screw-in access hatch lets you ventilate, pump out leaks, and even add water if you want to add ballast if you switch the canoe to a Pacific shunting proa.
NOTE: You will NOT glue the decks down because you might want to take them up for maintenance. Use silicone or polysulfide good, and screw them down. I added one 6 inch commericial screw-in deck plate for access and ventilation.
Step 9 -- You can glass the outside of the ama as you glass the deck pieces. I also added an oak strip on the keel and heavy glass tape, since this keel can take a lot of punishment.
Photo 3 -- Epoxying on an oak rub-strip to the ama "keel."
Photo 4 -- Adding heavy 17 oz glass tape to the bottom of the ama for abrasion resistance.
Photo 5 shows completion with epoxy-graphite mixture.
Step 10 -- Prime and paint. I epoxy soaked the interior.
Step 4: Finish the Basic Canoe Configuration
In this step you finish the basic hulls (sand, paint), build the crossbeams (akas), and set up the vaka-to-ama height relationship by (a) thinking about it well during the critical phase of "drive-way sailing" -- setting the boat up in your yard and "sailing" it during a literal "dry run" (never skimp on the drive-way sailing, and in fact do it on some windy days to see how the sails and rigging behaves), (b) testing the reality on the water, and (c) making final adjustments.
For step B, if you did not go ahead and build rudder, leeboard, and sailing rig, you will want to put in the equivalent weight to sink the vaka to its sailing waterline (with you as the crew weight). I suggest at least 40 pounds to account for the foils, paddles, masts, spars, sails, and other gear such as clothes, food and water, and anchor/rode. Better still actually find out what these things will weigh.
I chose to bring the boat on the water before I had all the sailing gear ready. The preliminary float test will convince you that the effort has been worthwhile, and the further efforts will pay off. Of course, you will temporarily lash the crossbeams to the ama struts (I used a Spanish windlass/twist sticks), see how the boat floats with you in it, then raise or lower the ama attachment points as needed.
If you did what I said, you made the ama struts long so the adjustment will consist of cutting them down to the right length. You will note I didn't do that. I was cocky or lazy, I don't know which. Maybe both at different moments since neither cockiness or laziness effects ultimate causality. Anyway, I was lucky and the canoe floated around level with sailing weight in the vaka. I did cheat a little by using the free version of Hullform software to learn better how the ama would float on its waterline.
Photo 1 -- Laminating the akas from tongue-and-groove Douglas fir flooring planks. These planks are good resources for projects that need clear, dry wood without having a REAL lumberyard nearby. Big box home stores will carry them. Adz and grind off the tongues and grooves, epoxy laminate with lots of clamps and/or weights, and give the corners large, aerodynamic radiuses with a jack plane. I tapered the akas from 4 to three planks (ama-end) with smooth merging achieved with draw-knife and sanding drum on electric drill. These akas are simply raw strength and weight. I do not mind weight here so much: if the akas break, you are fucked. Please study that powerful word, imagine yourself in an outrigger canoe with a broken outrigger, and understand why I used it.
Photo 2 -- A view of the completed hulls; how and where they will fit together under their design loads is the challenge at this stage. Your ama struts that will attach to the crossbeams should be left tall and unfinished unless you are really confident in their required height. I already had some experience with this issue during the construction and use of my first outrigger canoe, so my cockiness was based just a little in experience. The canoe need not float perfectly level, especially a sailing canoe whose attitude will be constantly changing in pitch and roll planes.
Photo 3 -- Here I am in the first float test. The vaka and ama matched well enough in height relationships, and I could finalize their attachment scheme.
NOTE: This is a fairly deep hull and not meant for a lot of paddling. The hull depth suits my salt-water sailing grounds out of New Haven, Connecticut, where the waves are often short-period and steep, frequently 3 feet high and sometimes coming over the bow. And in fact the bow could be a few inches higher I suppose. I also like to be able to sit "normally" (kitchen chair normal) because that's what my back likes best in its middle-age. As well, I want to be able to stand in the cockpit momentarily with my knees inside (a safety feature). I intend to deck-over the canoe hull eventually (thwart height with 6 inches of topsides to recline inside) but I will retain one full-depth foot well for sitting and standing. You need to think about your personal ergonomics and uses for the boat when you design it.
Photo 4 -- The ama-to-vaka attachment scheme is a lashing, which is the traditional method in the Pacific and an excellent. I have sailed the canoe two reasons and left the lashings as I first secured them. They tend to be trouble-free. Use good quality line (1/4 inch Dacron is what Gary Dierking, an professional outrigger designer and builder, recommends for small canoes. Get his book, Building Outrigger Sailing Canoes, which details the construction of three sailing/paddling canoes, in both tacking and shunting sailing modes.). Make sure you glue in extra thicknesses of wood in the areas undergoing the strains of lashing line, and make sure you smooth and round off (radius) the holes and corners through and around which the line will go. I recommend coating those areas with epoxy to soak into the wood and contribute to forming a smooth hard surface. Note the oak locating pin (here not yet pushed in) used to take the lateral strain of sailing ama-to-leeward.
Photo 5 -- The ama-to-aka lashing: I installed stainless steel eye-bolts (see the photo) on which the ends of the akas rest. The lashing line goes down through the solid wood of the aka, through the eye-bolt eye, around the ama strut, and pulls the aka onto the eye-bolts (or rather, into the corner formed where the bolts penetrate the upright strut), wrap around the horizontal parts, and cleat off on a cleat out of the way under the ama strut cross-piece (horizontal). The lashing shown here was temporary during the mock-up of canoe assembly.
NOTE: Attaching the akas to the ama has occupied centuries of philosophic thinking in the Pacific. You will know why once you build an outrigger canoe; however, I think many of the attachment schemes of Pacific tradition were adapted to the specific use of the canoe and its waters, the materials available, and even perhaps the subtle needs of ethnic identity marking. Feel free to experiment with the attachment scheme. Mine works well enough, but if I changed anything, I would think this area over one more time.
Step 5: Build the Sailing Gear
NOTE May 2011 -- Last year I changed the steering method to a traditional stern rudder: a cheek-piece attached to stern with canoe-stern gudgeons/pintles bought from Duckworks Magazine with a 1/4 inch thick aluminum plate for the rudder blade, attached with a 1/4 inch SS bolt. The heavy blade kicks up when it hits something and falls right back down again. I used a rudder-yoke-tiller-linkage to get around the mizzen mast. I like this better -- the boat steers a little better, but as ever, once the rudder is at the stern, you cannot easily repair it at sea.
ANOTHER NOTE: Safety-wire the rudder-blade bolt! I take it off when I trailer the boat, so I used a finger-tight nut on a longer-than-needed bolt, which caused no problems during my day sailing. However, during the Everglades Challenge the nut spun off after about 22 hours of nonstop sailing (thus no chance to inspect), the rudder blade fell off, and I had to drop out in rough weather (where you really need a rudder to steer around breaking waves). Yes, I had had a plan and even gear to safety the rudder, but I neglected to do so in the rush and excitement of the starting line. A 50 cent part cost me everything (which was a LOT!).
You will need a rudder, leeboard, mast partners, mast and spars, and sails. I bought a pile of used fiberglass windsurfer masts that I used for masts and mainboom, and made wooden spars from glassed Douglass Fir cut out of staging planks from the edges (making the wood blanks essentially quarter sawn = good).
I built rudder and leeboard out of those wide laminated planks that home stores sell for shelves and desktops. The lamination spreads out the defects if any (but you will choose the best pieces free of knots and sapwood). I shaped them to foil shapes with draw-knife, planes, belt sander, and orbital sander, then glassed them with 6 oz cloth.
I captured the leeboard between hull bearing pieces on the inside and rails on the outside. They thus look a little clunky on the hull, but this method is versatile. I designed this set-up to allow about 40 inches of of fore/aft movement around the center of the hull, so that the boat's center of lateral resistance could be adjusted. Also, this lets the leeboard kick up when it hits something. The leeboard movement also lets me remove the mizzen sail and sail on the mainsail or by shifting the mizzen to the main partners for breezy weather sailing.
I decided on a quarter rudder because I wanted to try one. I liked the Indonesian style quarter rudders that Tim Anderson documented in his trip photos, and that led me to read the book, Outrigger Canoes of Bali and Madura, Indonesia. I made up a pseudo-Indonesian quarter rudder held down by a releasable lashing, and later changed to a hinged quarter rudder pivoting on a bolt. These playings around will explain why the rudder looks odd. It has undergone much experimentation.
Photo 1 -- Blanks for leeboard and rudder foils:
Photo 2 -- Planing guides to check progressing shape of leading and trailing edges of the foils (I opted for durable edges rather than efficient edges):
Photo 3 -- The gear and situation for shaping the boards; I used my beloved "nomad" toolbox/workbench described in another instructable;
Photo 4 -- After one season with an Indonesian-inspired steering oar/quarter rudder, and switched to this hinged quarter rudder (here, roughed out). The lashings come from version 2.0, using a Wharram-style figure 8 lashing hinge/bearing. This method probably works best on a long catamaran stern; for me, the lashing surface was too short and the torque on the rudder too high, and my nylon line too stretchy. Version 2.1 opted for rudder hinges from Duckworks. I am still not happy with the rudder here though it does work. It has too much lever-arm making too much force on the tiller. I need to start over with a rudder designed to be a kick-up rudder, not an Indonesian-inspired board pressed into service because I was lazy.
Photo 5 -- The rudder in stowed beaching/trailering position.
Photo 6 -- The forward mast partner and board with eyebolts for turning and attaching the halyard and down-haul blocks; the downhaul is not installed in this photo, but it is a two-part downhaul to get some power to pull the tack of the sail down and get the right tension from tack to peak. The windsurfer mast here is too bendy for a lugsail; I will replace with a 2.5 diameter aluminum or glassed over DF mast. When a mast bends under a lugsail, more draft is put into the lugsail, which is bad in windy conditions.
Photo 7 -- A view of the assembled canoe from above to show the interior arrangement (I sail from the aft cockpit, and later I added rails across the akas on which I installed a sliding seat for hiking out. The seat slides forward to make room for paddling (seen in the capsize test photo in the last step).
Step 6: Go Sailing to Restart Your Priorities
Photo 1 -- I bought sails from The Wooden Boat Store; the main from the Shellback Dinghy and the mizzen from The Nutshell Pram (54 and 37 square feet respectively). This rig keeps center-of-effort low which reduces capsize risk, and they are great for a beam reach. You can find instructions in Marino's The Sail Maker's Apprentice for building all sorts of sails (and see Tim Anderson's instructable on making a sprit sail out of cheap polytarp on this site).
The lugsail is not the best choice for going close to windward, nor is a cat-ketch rig the best for windward work. I get about 55 degrees to windward course-made-good at respectable speed, which is not unusual for a low-tech cat-ketch rig. The boat will of course point higher, but speed will drop drastically. Pinching up as high as possible will drop speed to about 3 knots (depending on the sea state).
Could I improve mediocre windward performance with increased skills? Maybe. Hard to say where skills end and physics begin, and vice versa. Suffice to know that an outrigger canoe is sometimes better at going very fast at lower windward courses rather than pinching up to go slowly at higher windward courses. When this is not true, you are heading for rocks and need to sail as high as possible at whatever speed. Doing 6 or 7 or 8 knots at 55-60 degrees is much more fun than pinching up at 3 or 4....if no horrific obstacles threaten.
The shakedown cruise will sometimes be frustrating if you expect too much. Expect lots of problems, and it will seem good. Mine was good though I had things to learn about tensioning the downhaul on the standing lugsails, and setting main and mizzen for best drive to windward.
I immediately found that the canoe was pretty fast, relatively. The rig's center-of-effort is low, and that protects you somewhat from capsize -- but when a small outrigger is ready to capsize, it is going over, often pretty quickly, and that's that. This canoe beam is only 7 feet, so you can capsize the Short Dragon easily in a brisk wind if you think you can just sit comfortably in the main hull and sail from there. In fact, usually you can sail it while sitting facing forward sitting in the thwart, perhaps even leaning back against the mizzen mast, as comfortable as sitting on your kitchen chair.
But on a good breezy day, you will want to sit to the side on a side-seat, on the ama-side, at least. My most rapid sprints have been with the ama to leeward, being pressed down into the water while I am sitting in the canoe hull. There is enough ballast to windward in this mode to prevent a capsize but now the threat is pushing the ama under and tripping the boat. I have hit a 14 knot high (a rare event, conditions were perfect) and it was very exciting, with the ama seeming to vaporize the water at ama's bow -- but disaster is near! A new ama shaped with most displacement in the forward part will make these high-speed sprints safer.
Photo 2 -- Early on you need to do a capsize test on a calm day. How long will the boat float knocked down? How easily will it right? How long will it take to bail out? And understand -- your discoveries will not apply much for a capsize in high wind and rough water! I suggest getting in a wet suit on a lake on a rough day and trying it again. I had two large foam blocks under the thwarts and some in the ends. They let me sit on the flooded hull up to my waist in the water. I righted from that position; but if you slip off the hull first then right the boat with a line on the ama (Watch your head! I have experience in this! Watch your head!) the canoe hull will scoop up less water as it rights.
NOTE MAY 2011 -- Last year I decked in the canoe, leaving the hull open only udner my seat and the footwell. The decking is ~6 inches under the gunwale to allow for a sleep deck 9after the footwell area is covered over with a filler piece). I installed a 14 inch diameter Bomar hatch in the center compartment for a large watertight storage space. (You can see some of this at www.wtarzia.com, click on "outrigger."). The boat is a little more seaworthy with these changes, but also heavier -- the vaka (main hull) is about 200 pounds, very heavy for a boat this size. I slept on the sleep deck one night at anchor, and it is coffin-like, but OK if you are exhausted.
The boat righted easily but took 15 minutes to clear with bucket and pump. If any waves had been present, the hull would have filled again. I have yet to roll the boat 180 degrees and try to right it. I Realistically, only an enclosed hull, with perhaps a small volume used as a foot-well for comfortable sitting and standing, has any chance of being bailed out in rough water.
Photo 3 -- When the wind dies, and you drift on a circus mirror, friendly wildlife (well, how wild can it be?) may come to visit -- then you redefine yourself and your works as being one among a diversity of eco-niches (you don't need to see the film Avatar for that -- here a duck and her kids insisted I was their eco-niche).
Photo 1 suggests you can take your place amidst the local color of maritime tradition, and you can thank yourself. Now you fill the role of the people you have often seen from a distance and were envious of. Today it is your turn, and a day like this makes up for a lot. (photo courtesy Ms. Seluga).
Step 7: Convert to Trimaran
I built curved box-beam akas to get the two amas to just touch the surface of the water with my weight and expedition gear aboard. The total beam of the boat was 10 feet (Everglades Challenge races require narrow beams to get through bridge "filters" though the old filter at Gasparilla is now gone, and the new bridge is wider). These are made with solid wood upper and lower parts, and plywood sides, with solid wood spacer blocks to strengthen, using epoxy glue. Gary Dierking's book, "How to Build an Outrigger Canoe," tells you what you need to know. They are light and strong. I used douglas fir tongue & groove ceiling planks (with the tongues and grooves cut off and planed true), which can be bought clear and dry from most lumber stores. NOTE: Dry fir can split easily, so pick through the pieces before purchase and inspect closely. (Photo of these akas before final piece glued on shown below).
I used ratchet straps to conect the inflatable amas to the akas (bought from NRS). The result was a fine almost "instant" trimaran (for the cost of the amas, which are not cheap), a very light boat, that took me through some very rough ocean. The trick with setting up the relationships of a double-outrigger is let the amas just touch the water at rest at sailing load. When sleeping at anchor (which I did one night) the amas will not slap the water much and annoy you. Under sail, the wind will heel the boat over, pushing one ama down and lifting the windward ama, and your wetted surface will be reduced, and hopefully the lifted ama will not catch wave crests and spray you. Test and adjust on calm water such as a lake! Carry filled water bottles to simulate your typical gear load.
Result: I was very happy with the boat! My first sail with it was at this race, but there were no bad surprizes. I sailed sitting on the aft seat, facing forward, very comfortable, with light helm. My rough designing and guessing worked out by good luck. The buoyant amas worked great through some rough sea (at one point, sharp, short-period 4- and sometimes 5- foot waves in shallow water in a 25 mph squal). My rudder blade fell off (forget to safety wire the nut) so I dropped out of the race, but I spent 27 continuous hours in the canoe, and Short Dragon did not disappoint except for paddling performance -- the square hull and heavy construction is not paddling-friendly -- I paddled several hours and averaged about 1.7 knots. (Finished boat photos below).
I hope to write a separate Instructable on this if i can find time.
The photo of me taking off from the beach is courtesy Tom Ray of www.tropicalboating.com ; please visit his site! -- WT