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.

Mistral Haul-out

Those who say a wooden boat is a lot of work are right.
Mistral has not been hauled out for maintenance and new paint for two years, which might be twice too long. Anyone who has paid for a boatyard haul-out knows why I waited! Not to mention all the work involved.

1000 square feet of weather damaged paint has to be scraped, sanded, repaired and painted. And the happy boat owner/builder has the good fortune to paying for this privilege. Each year takes it's toil, so it's a crap-shoot whether skipping a scheduled maintenance is worth it.

Doryman has been accused of having a very low tolerance for sloppy maintenance.

With a full length keel, Mistral sits easily in the cradle of the hoist. Dories are adaptable to any situation! Isn't that the greatest accolade?

It's just about sunset on an overcast summer day, while Mistral hangs in the slings.

Greg, if you're out there, now's the time to survey the old girl! She's on the hard at Riverbend Boatyard. And Doryman will be there every day for three weeks.

Mistral in the sling from michael bogoger on Vimeo.

Meditation and Transformation

It's quiet here today. I just returned from a walk with the dog. She's the offspring of a spirited Border Collie, bred with a Blue Healer. She doesn't care much for calendars or clocks, and lives from moment to moment, the all too infrequent romp in the woods. I strive to be more like her.

Heather left long before daybreak, to work at the bakery, serving the gluttonous masses. In silent meditation, I've decided to fast in contemplation. I live in a country so preposterously prosperous that being thankful for good fortune seems hypocritical.
The rain comes down in buckets, as we say, out in the boatyard, and though I spend most days out there working in all weather, it seemed appropriate to set the tools aside for awhile. In a bit, I'll go out and bail an old carvel-planked boat that is kept open to the weather, to keep her planks swollen and tight. Her other, more protected sisters will be patted down and reassured their lives will not always be spent on the hard. My neighbors see this ritual as tedious, but I do not - it is a meditation for a sailor between voyages. It is said the professional sailors of old yearned for the sea the day they returned home. I once knew an old fisherman who, while in port, would visit his boat everyday and sit at the helm, reading and listening to the marine broadcasts. I can relate.

Remember Mistral, the big live-aboard/cruising dory that inspired the moniker on the header? She is still around, though an apparent permanent resident of the backyard boatyard. We hauled her from the water a couple years ago to make the journey from the Oregon coast to my new domicile in Port Townsend. Why didn't I sail her here on her own bottom? You ask a good question. The best answer I can offer, is, a trip northbound on the Pacific coast of the US is strenuous, since a vessel must climb uphill, against prevailing weather and tide. I've done it a few times - and failed, too. It's not a voyage to be taken lightly.

A vessel must be redundantly reliable for an open ocean passage.
Mistral suffers a limitation due to poor design and it's nobody's fault but mine. (Oh how hard it is to say that...). I gave a lot of thought to accommodations, structure and sail rig, but just let the cockpit and steering happen on it's own.

Over the years (how quickly they pass), I have struggled with different steering options, going from a simple tiller, to a wheel, and when that failed, back to a tiller. The hard truth is, on a double-ended vessel, the cockpit can be pitifully tight.

So, deciding to finally do something other than going from one haphazard solution to another, Mistral's surgery has begun. First, I've taken a hardtop bimini from an older boat and covered the helm seat. Next, I sawed the old transom off. You heard me right. The languid angle of a dory transom is simply too low for a stern mounted rudder. In a tack, the rudder lifts to the surface of the water, losing purchase and the unfortunate vessel stalls. If the dory doesn't have enough weigh, it is soon in irons. I could have designed a balanced rudder, but am disinclined toward underwater holes in my boats. So now, Mistral's stern is more vertical. I really love the diminutive V shaped transom of a traditional dory, so this was a hard choice. The change is not severe, in an attempt to keep that aesthetic.

To add more seating for the helmsman, I've taken liberties suggestive of traditional Asian sampans. Since I usually sit up on a very skinny shear rail while under sail, I've added a platform, up under the bimini, which my friend Martin calls the poop deck.

I apologize for the poor quality of these photos. Like I said earlier, the winter monsoons have arrived, which means, if I'm to get any time in the boatyard, I must work under a tent.

 Meditation and transformation to keep a sailor sane, while ashore.

Photo courtesy of Mathew Atkin

Mistral's New Mainsail

It's been six months since the scheduled completion date for Mistral's new mainsail. Not too bad, in the context of boat building!

The mast and boom were finished three years ago and Mistral has had an old, used handed down sail until now. Lynne Fabricant of Sailmaker's Art machine sewed the new sail and hand sewed the tack, clew and reef-point cringles. All that remained were the reef point eyelets and bending on the sail track slides, which were also sewn by hand here at home.








It's been a busy week and all hands have been piped to duty.







Below: A reef cringle, a reef eyelet for a nettle and a leach string jam cleat, all sewn with waxed sail twine.










There are still a few details to fine tune on the sail, but there was enough completed as of yesterday to hoist the main and make some calculations for the length of the reefing nettles.




This sail is my own design, so there has been quite a bit of trepidation about how it would work out.

Of course, Lynne's work is impeccable. It was with no small relief that the new main fit as designed and set beautifully! With some fine tuning and a bit of decent weather (could be a while!) and it will be prudent to test Mistral with a full suit of fresh sails, for the first time!

Ever wonder how to hand sew a reef-point eyelet ring? Like watching waves on a beach...

Sewing a Reefpoint Ring from doryman on Vimeo.

Live-aboard Dory

DoryMan has been receiving visits from a discussion on the WoodenBoat Forum lately on the subject of St Pierre Dories and live-aboard dories in particular. But the Forum will not allow me to respond. Imagine that.

So, this is for you folks who come here looking for information on dories. Mistral is my own dory-cruiser and a fine live-aboard she is. She is my own design and I built her (by) myself. She is 36 feet LOA with an eleven foot beam and displaces five tons. For those contemplating such a task, let me warn you - it will take a lot of energy, time and commitment. At times, I was on the verge of cutting Mistral up for firewood.



But to live your dreams is worth every minute. In fact, I am convinced there is no other way to live. That's why I write this blog - to encourage others to live their dreams. It does not matter if you don't know what you are doing - you will learn.



Mistral is not a St Pierre Dory, but similar. Her bottom profile is flatter, which gives a comfortable walking area below (the St Pierre has the most severe bottom rocker of all the dories and walking around in one can be a challenge). For those who are contemplating building a St Pierre, we have been following two different stories this last year, click here.





You are encouraged to add to the comments at the end of this post (or any post - I love to talk about boats!) Or contact me: mbogoger(at)gmail.com if you have a story to share.



Images of Mistral under sail can be found here.
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Mistral's New Mains'l

It's been twenty years since the inception of the dory cruiser Mistral. She's been afloat for almost five years. Last weekend marked the completion of the design.

That's a long time. Thinking back at all the things that have happened in those years, both personally and over the world, it's a completely different place. There were times when this big dory was a burden, an unfinished hulk... Almost chainsawed it into scrap twice.






But more than anything, it's been good therapy.

For the last five years the sail rig has taken shape organically. Starting with a salvaged mast and used sails and ending recently with a new custom made mainsail. After weeks of hand sewing finish details, the sail was ready for a test on Sunday last. The crew showed up, the sun came out from behind the clouds and we went sailing.

There was no wind to speak of, but opportunities came and went for checking the set of the canvas and the drive of the ship. Snacks and champagne (Chuck brought his prize winning smoked salmon!) were passed around the cockpit. Therapy indeed!








My good friends Kim and John came out in their skiff and took photos. Kim is just learning to use her camera and she has an excellent eye. Thanks, Kim!





And thank you Chuck and Rick and Shay and Mary for excellent camaraderie, good food, hard work and helpful design improvement suggestions!

Mistral on the River from doryman on Vimeo.

I'd also like to thank all of you who have offered encouragement and interest in this project, since the beginning of this blog. The idea behind this journal was to document Mistral and her cousins and it has turned into so much more.

It's been a blast!
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First Launch

An exciting day for Doryman as Mistral is lowered into the water for the first time. Since she is designed and built solely by Doryman, there is a fair amount of trepidation and anxiety about how this will turn out! Any boat builder will tell you that seeing their creation float for the first time is a huge relief!
Note the outboard in the motor well. Mistral's auxiliary power is a 9.9 hp Mercury "Sail Power". This is a small motor for a 36 foot, 5 ton vessel, but the hull shape is a very efficient one, and Mistral will make an honest five knots with this motor at two thirds power.

Winter at the Boathouse

It seems there are plenty of people around who paddle and row all year, despite the threat of torrential rain and temperatures barely above freezing.








Just such a group gathered upriver from the Community Boathouse in Toldeo, Oregon yesterday. As fate would have it, the weather was barely winterish. Temperatures were in the mid 50's, fahrenheit and not a drop of moisture fell from the sky.






Doryman was there in the dory cruiser SV Mistral. Though we've seen this stretch of the Yaquina River many times before, Mistral has not. This big dory was designed to explore shallow water, yet a low bridge blocks her mast about thirteen miles inland from the ocean. At the moment, I'm working on a system for raising and lowering her mast while underway. So with the rigging down, we took the opportunity and joined those fortunate who took a chance on the weather to catch the most extreme tidal ebb of the year for a joyride downstream.





Most of November in coastal Oregon has been very wet, with record rainfall. The Yaquina is nearly a foot above flood stage and rising. Couple that with a twelve foot tide drop and you have plenty of current to push a big boat. I have a long sweep oar on Mistral so I can lean back on the tiller and thus row and steer at the same time. Couldn't keep up with the smaller boats, though.







This event was in support of the Port of Toledo's Community Boathouse Project. We were going to have a potluck dinner afterward in the Boathouse but everyone opted instead for the barbeque ribs at the brewpub across the street. Fortunately for everyone, we were the only (25) people in the restaurant.


















Many of these photos are compliments of Andrew Linn, who is the spark plug for the Boathouse Project. That's him just up and to the right, preparing to cut across in front of a five-ton boat.
Better hurry, Andrew!

The Toledo Community Boathouse is sponsored by the Port of Toledo.


The full story, in pictures.....

Building "Mistral"

In 1990, I started building a 36 foot dory. It has been a long process, with many shifts in priorities, but the boat is finished and is the inspiration for this blog.
SV Mistral was not originally intended to be a sailing vessel. The concept was a shoal draft, live aboard/ camping boat that would move efficiently through inland waters. The impetus to finish her as a sailboat came from friends who recognized the potential in this simple, efficient design. Though she has not yet been tested, she is more than an inland water camp boat, but a capable cruiser and comfortable liveaboard. In the eighteen years since the inception of this craft, I have designed, built, and restored many other boats, but none have given me so much. I couldn't begin to guess how many hours went into building this boat, but it was worth every minute. The next few postings will introduce an overview of building Mistral

Laying up the keel with the proper camber, or "rocker" is the first step. The first pictures in this set are scanned from old and faded photos, taken with a dusty, dirty shop camera. Bear with me?

Mistral gets her mast and rigging

"On the hard", Mistral is rigged for sail. The mast is set in a tabernacle on the leading edge of the main cabin and can be raised and lowered as needed. The lowered mast rests in a cradle on the stern of the boat. This picture was taken during Mistral's haul-out, the summer of 2007.
I call this design the "Pemaquid" after the promontory in Maine, the area where the successful design used in this boat was developed for the cod fishery. Dories were lowered from larger boats and propelled by one or two fishermen, at their oars, over the schools of cod on the Great Banks.
The sail rig is more the skipjack type with a very low aspect ratio. With a long boom and a full keel she will be slow in stays, but sea worthy as a Stormy Petrel.

Mistral, a Sail-Rigged Dory

The SV Mistral is a shoal draft cruising/live aboard. She has been a labor of love for Doryman for eighteen years. In this photo the completed vessel lies quietly at anchor on the Yaquina River in western Oregon, USA.

Mistral Voyage

Yesterday morning Captain Rick and The Lady Cat accompanied Doryman 13 miles down river on the beautiful Yaquina.
Mistral embarked at 0520 in the morning dark and fog. The sun was slow to rise this close to the Equinox and even when it did, with all the fog, visibility was almost nil.











The Dory knows her home waters though and the day broke calm and silent, full of marine mammals and wading birds of all descriptions stirring for breakfast.









Even within the mouth of the river where the highway passes between ocean and sheltered waters, the Yaquina Bay bridge was barely visible beyond the breakwater.
















0800 hours and back in Port.