New Mainsail

Mistral is getting a new sail. For the last couple years, since the mast was raised she's employed a handed down mainsail, which is smaller than the design size and quite ragged.

Doryman has been working on a sail plan (and saving his pennies) for a dory style Marconi main. The new sail will be sewn in a traditional cruising style with hand sewn rings, grommets and reef points. The clue, tack and head will be protected by leather chafe patches. A very salty sail, for an old salty dawg!

Lynne Fabricant of Sailmaker's Art is developing the sail to the specifications shown here, and Doryman will be completing the hand sewn details. (click on the image and it will come up a bit more clearly).

In a typical dory type mainsail the aspect is kept low, with a relatively short mast and long boom. In this case, the luff is 24-1/2 feet high and the foot 18 feet long. The idea is for the sail to provide power with a low righting moment, since the dory hull can be very tender. Too much weight (and power) aloft would be wasted and potentially dangerous in variable winds. The short sail allows excess wind and power to be spilled easily and quickly. With the dory's renowned reserve buoyancy, combined with a full ballasted keel, the boat will right itself immediately in a puff.

The low aspect rig was the first generation of the Bermudan style of sail, before the advent of modern materials in sails and hulls which allowed for the increased strain of higher aspect designs. For a working or cruising craft such as a skipjack or bugeye, the low aspect rig provided stability and ease of handling, reducing strain on craft and sailor. The designs of L.Francis Herreshoff also used the low aspect Bermudan to good effect, as in the the ketch Nereia.

The Sailmaker's Apprentice by Emiliano Marino was an indispensable reference in researching and developing the relevant details of a traditionally built sail. Since Doryman is trained as draftsman and architect, the plan is drawn in AutoCAD.

The details are being worked out for a new working jib as well, since all this sailing dory has at the moment is a storm jib. It's an exciting year for Doryman and his Mistral.

Stay tuned...

Hardangersjekte Valgerda Lug Sail

Last spring when I purchased the William Atkin Valgerda known as Reinsdyr she had been stripped of her inboard motor, sail and rigging. After some repair and extensive caulking and refinishing she debuted at the Toledo Wooden Boat Show, but as a rowing craft.

Meanwhile, back in May, I had ordered a new sail that has just now arrived.






The plans for the Hardangersjekte Valgerda as William Atkin drew them show a fixed lug sail with a moderate peak. The design sail area is 72 square feet. This seemed a bit small to me, probably as an auxiliary to a primarily motor driven vessel.

We all know how Doryman feels about that! For a boat of this size and weight I thought that the sail area should be no less than 100 square feet, but not much more since the rounded hull and dramatic rise would result in a boat that sailed hard-over. I also wanted a balanced lug with a higher peak in an effort to pinch to windward more efficiently. Damn the motors, full sail ahead!







Paul Gartside designed a beautiful balanced lug option for his Skylark that I like very much and it just so happened that my friend Lynne Fabricant of Sailmakers Art had just made that sail for a customer. She agreed to size the plan up from 88 square feet, sent me a drawing for a 119 square foot lug sail and contracted to make it up in tanbark.


The sail is one more example of Lynne's quality work. Regular readers will remember she made the mainsail for Mistral and it is also perfect.





I hoped to make up the rigging from the plethora of salvaged gear stored out in the boatyard and it looks like it's going to work out fine. The mast is nearly fifteen feet long, made of old growth spruce. It has been with me a long time. A good friend salvaged it years ago and traded it to me (thirty years or more, no kidding!), but until now it has not found a home. It's been used for different applications which are evident in many old mounting holes for cleats. They've all been plugged meticulously though I never quite trust a plugged hole to be as strong as original so hopefully this will work out. The mast is a true collector's item with tight grain like you've never seen.






The yard is also spruce. Much newer stuff, though I've carried this around for thirty years too. Also salvaged from an old mast.
I pieced it together with two long scarps so was able to pre-load it with a bit of a curve to resist the tension that a yard like this is susceptible to. For the same reason, a bit of an upward curve is cut into a sail with an upper yard to help keep the sail from sagging as wind increases and sail tension pulls the yard down.

In this way I could keep the size and weight of the yard to a minimum.



The sail will be loose footed with a boom. I have an old spinnaker pole that will work beautifully. You've heard of the fellow who built a boat to match a nice pair of oarlocks he had?........





With the epoxy still curing on the sticks, I was compelled to set the new rig up and see how all of the calculations worked out. It's very cold and wet outside, so setting up on the boat was out of the question. What you see is the best I could do. Sorry if you were expecting photos of a Hardangersjekte under full sail, pushing a bow wake.





That will have to wait but I promise,
Soon.




The dog is trying to tell me she can't reach her bed which is the blue rug under the head of the sail.
She wasn't anywhere around when this project started.

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Mistral Design Revisited

There are a few nascent dory designers who have written to me with comments and questions about designing and building Mistral, so I’d like to talk about that in a little more detail, hopefully answering some of those questions. (The rest of you, please humor me…)


There are no plans on paper for the build of this boat -- I think you can get by just fine without true plans, because the dory is a simple boat that has changed very little in centuries and is tried and true. And before there was paper, the plans filtered down through generations by word of mouth and trial and error.

I think of wood boat building as sculpture. Each piece made in the process has to fit in complete harmony with every other piece, so it's essential to visualize the entire piece from the very start. Wood carvers will tell you that the material they are using defines the sculpture. Despite the mathematical rigor in boat design, every hand made boat is different from all others, even those made by the same person with detailed plans, since interpretation plays an essential part of the creation.
For me the design / build process is organic and develops in my head as the boat is built. The proportions of dories can be found in a variety of sources, but the boats are remarkably similar. For this reason I was confident, though I had never seen a dory as big as Mistral, the proportions from an existing table of offsets for a banks dory would translate smoothly into the much larger boat I imagined.
If you are drawing your own plans and feel intimidated about details, take heart! Jump right in, the details will work themselves out.

I don’t mean to imply that the boat built itself. There was a year of pondering and engineering to work out the scantlings and when in doubt, I erred on the side of overbuilding. Mistral utilizes modern truss framing and plywood for strength so, though she is a stout boat, she still required additional ballast to carry sail.

The backbone is a keel built of laminated fir 2x6. For the forward half of the boat, this keel takes the shape of the rocker, but for the aft half, it has a flat bottom combined with rocker and so becomes deeper toward the transom.
How much rocker is needed? There is the St.Pierre et Miquelon which has a very jaunty chine and even livelier shear, and is an active boat, buoyant and agile, thus so the Mackenzie River Dory, which can turn on a wave crest. The bateau or flat bottom skiff has almost no rocker and is less fidgety. The eventual use will determine how active the bottom shape of your dory will be.




Mistral has about six inches of rocker fore and aft, and is relatively flat for boat with a 30-foot waterline. It’s just enough, and she cuts through the water like an eel.

She has straight frames with sheet plywood and was originally designed with a 3/4-inch bottom, 1/2-inch hull, 1/4-inch cabin sides and 3/8-inch decks (all marine grade fir plywood). The frames are (clear grained) old growth Douglas Fir 2x4's at 17 inches center to center. I didn't feel comfortable with the 3/4" bottom, so laminated another layer of 3/4" for a total of 1.5". I would recommend this, since the weight down low is good for stability, and a flat bottomed dory should be able to support it’s own dry weight.






Since Mistral is to carry sail, she needs ballast. The ballast is in a box, made of half-inch plywood, poured full of concrete, with several continuous lengths of steel reinforcing bar, for structural integrity. The ballast keel weighs one ton and is aligned with the middle section of the boat, which, for a double-ended hull is the approximate center of resistance. The finished keel is 18” deep, which gives the dory a total draft of 2.5 feet.

Stainless threaded rod bolts the ballast to the wood keel and epoxy impregnated 10-oz. fiberglass cloth covers the keel and hull. The motor is mounted off center, so there was no need to install a shaft through the keel. The weight built into the bottom vastly improves the handling of the dory.




Mistral has an 11-foot extreme beam, which means that on the road, I need a wide load permit and occasionally, pilot cars. Fortunately I don't trailer her much! She weighs five tons and about two tons of that is ballast. I added (one ton) interior ballast with the new mast, because she was very tender.



The dory is a very buoyant boat by nature and rolls quickly from side to side, which makes people nervous. Once you know the boat, this feeling disappears, because the design is incredibly seaworthy and will always right itself. You learn quickly to keep your weight centered. The hull will carry an impressive load --- an additional ton of ballast raised my waterline only 1.5"!

Mistral has "raised decks". In the pictures, the knuckle you see is the true shear and the beam of that basic hull is 10 feet. There is added width in the raised decks (an additional foot), which I designed primarily to help give me standing headroom without having a tall, boxy cabin. This feature became apparent during construction and is an example of how a plan will develop.
The beam at waterline is approximately six feet, which is a positive influence on efficiency, but contributes to lively response.

With Mistral’s low aspect sail, she goes like a greyhound on a reach or downwind, but with a full keel, she is slow to tack.
I run a 9.9 hp Mercury four-stroke “Sail Power” outboard in a motor well, which pushes the boat along at about five knots and is a testament to the efficiency of the double-ended dory hull. This oversized dory will cruise at this speed for 7-8 hours on a small three-gallon tank of fuel, with this small efficient motor.
A full sea trial is still in the future. I intend to petition my friends as crew. Any takers?

The mainsail I ordered for Mistral is still at the sailmaker's - I think I hit her at a bad time of year. So, I'm still using an old hand down main, which is too small for the boat. I recently adapted a used jib (Lashed on some hanks – That was fun!) which seems to work just fine (the one I had is now the storm jib). So things are improving. I made an up river run from the boat yard last week under jib alone (running with the tide) and averaged five knots! There was too much stuff (paint cans and etc.) to get the main out.




There is a great book about building the St.Pierre et Miquelon by Mark White, published in 1978 by International Marine Publishing. It is probably long out of print, but a real jewel. Mark builds a planked St. Pierre in Alaska (outside!) and documents it with pictures and a text intended for commercial fishing vessels. He recommends a 10 hp Saab or 10 hp Volvo Penta. He says the Saab has more torque, but the Volvo is much more economical.
To carry the weight of the inboard, Mark widened the transom eight inches, top and bottom, then fared that extra width forward to just past amidships. This added buoyancy and stability in the stern.



I wish I had widened my transom a little, too. I love the double-enders, but the cockpit is narrow just where I need the room for jib sheets, main sheet traveler and such. With the motor well in the cockpit, my big boat has the working room of a much smaller vessel.





There are design changes going on in my head all the time. If I were to build this boat again, it would look much different. But I won’t bore you today.

Please check links to other posts detailing the build of Mistral for additional information.

I’d be interested in hearing from others who are designing their own boats. The process involved is similar for all types of vessels and we can share comments and feedback.