Review by Carl Goy
cgoy@att.net
I bought the first edition of this book a year so ago out of curiosity after reading some of Barend’s “Boatbuilding With a Difference” series in Duckworks Magazine; I found it to be most enlightening regarding the development of hull shapes.
With the book’s second and latest edition, Barend Migchelsen has produced a delightfully simple explanation of the classic dory and skiff forms and how to reproduce these designs with little or no mathematics. In fact, if you can draw a rectangle and right angles, you can design a double-ender, a dory, or a squared-off transomed skiff exactly to your liking.
The premise of the book is that the dory and skiff are formed by intersecting cylindrical sections. That means that the sides of the boat are of constant flare and that the sheer line is formed by the top of a section of a cylinder. Don’t get lost here...imagine that you take a sheet of plywood and bend one of its long edges into a shallow circular arc. The whole sheet is now a cylindrical section because plywood only likes to bend in one direction at a time. Imagine again that you take a second sheet and bend its top edge into an identical shallow arc, but in the opposite direction. Now imagine them intersecting at an angle so the tops of the intersection of the sheets form a bottomless dory. Add a gently rockered bottom at your desired distance below the sheer and you have a dory! A skiff is simply a dory with one end cut off and closed with a flat transom.
Barend’s premise is well borne out by his measurements of a number of classic dories built with molds that have been handed down through generations. Amazingly, his theoretical dimensions and actual measurements of the dories don’t vary by more than an eighth of an inch.
The book is divided into three parts: one describes “The Simple Mathematics of The Design,” the second describes the construction of models and a skiff, and the third summarizes the design system and provides details for building a punt and a Laser-like
daysailer.
The “Simple Mathematics Of The Design” are as elemental as the afore-mentioned rectangle. Draw the half breadth of your boat as well as its height as a rectangle as seen looking at the bow of the boat. Add some bottom rocker, sheer and flare dimensions, and you have the basis for your boat. The only math involved beyond pencil and paper is Pythagoras’ theorem: a2 + b2 = c2 where a and b are the sides of a right triangle and c is its hypotenuse or diagonal dimension. (Any $10 calculator these days can help you solve Pythagoras’ theorem if you are not mathematically inclined.)
A few quick steps on the calculator will generate all the points on the rectangle that you need to describe the boat. Dividers – or a tick stick if you’ve drawn full size - can then transfer the dimensions directly to molds, side panels and bottom panels. Since the elemental shape of the sides is a cylinder, all the surfaces are developable naturally without resorting to twisting or torturing your sheet of plywood. The section on finding and cutting accurate stem bevel angles is worth the price of the book alone.
The second part of this slim yet extremely useful book will guide you step-by-step through building a dory model and through the construction of a full-sized dory-skiff, the dory with the squared-off transom. What I found most interesting were the tips and hints about wood, construction techniques and the touches that set the boat off from the basic lumberyard boat. Instructions are also included for turning the skiff into a sailing skiff. Simple details describe making a mast step, centerboard or daggerboard and trunk, rudder, spars and inexpensive sails.
The last section includes design details and instructions for building a 13’ punt and a 12’ Laser-like cartopper. The meatiest part of this last section is the chapter on “The System,” a brief recap of the design process. I can’t emphasize strongly enough the simplicity of Barend’s design method.
In conclusion I must admit that my profession is Electrical Engineering and that calculations and manipulating arcane formulae come as second nature. Yet I take great delight in simple and clear explanations of what would otherwise seem to be difficult concepts. Barend has
succeeded in the most simple terms of describing how to develop a hull shape. Rest assured that there are no calculations or concepts to fear in Barend’s Handbook. You will be able to design and build your boat in very short order.
cag
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