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cross-section, rocker, hull symmetry and taper.


Cross-section—Initial and Secondary Stability


The cross-sectional shape of the bottom and sides of the canoe will influence its performance, especially its stability. Stability is divided into initial (primary) and final (secondary).


Initial stability is what you feel when you first get into the boat. In a boat with great initial stability, you can stand up and walk around. It takes a lot of effort to flip this boat on flatwater. It resists leaning until it reaches a point of no return, beyond which it quick- ly upsets without much warning. That’s because sec- ondary stability was sacrificed for the stable platform providing initial stability. Secondary stability refers to how the boat behaves as it tilts. A boat with great secondary sta- bility feels stable and predictable when on a lean. This is a useful characteristic for whitewater moves, rough-water paddling and soloing.


Flat-bottomed canoes offer great initial stability at the expense of speed and rough-water perform- ance. Very secure on calm water, they’re great for sportsmen and recreational paddlers.


Round-bottomed boats are the other end of the spectrum. Perfectly rounded bottoms allow for clean entry and exit lines and minimal surface area in the water. They have great speed and efficiency but virtu- ally no initial stability. This is why rowing shells are round-bottomed but canoes, except for a few fast, specialized designs, usually are not.


Most canoe designs are a compromise between flat and round, with shallow-arch or shallow-vee bot- toms. These designs sacrifice varying degrees of ini- tial stability for good secondary stability and all- around performance.


The cross-section of some canoes is modified by the addition of a keel. A keel is a moulded ridge or attached piece of material that runs the length of the canoe on the bottom outside of the boat to help the canoe track and resist the influence of crosswinds. Keels are most often found on short, wide canoes used for recreation and sporting. They are undesir- able in whitewater because they reduce manoeuvra- bility and are vulnerable to rocks.


The sides of the canoe are either flared, turned-in or straight. Flared sides shed water. Tumblehome describes the shape of a canoe with turned-in sides. Tumblehome results in a narrower beam at the gun- wales, making it easier for the paddler to reach over the side of the canoe when paddling. Straight-sided canoes are a balance between the paddling efficiency of tumblehome and the dryness of flare. Canoe designs will incorporate one, two or all three of these in different areas of the hull.


Rocker—Tracking vs. Manoeuvrability Viewed from the side, the amount that the canoe’s


keel line (the bottom profile of the canoe) curves upward toward bow and stern is termed rocker. The amount of rocker determines how easily a boat turns versus how well it tracks. A straight keel line (no rocker) allows for exceptional tracking, ideal for cov- ering long distances in a straight line. A canoe with a lot of rocker offers exceptional manoeuvrability.


Hull Symmetry and Taper


Viewed from above, symmetrical canoes have identi- cal bow and stern ends with the widest point at the centre of the hull. This design offers more versatility because it can be paddled as a tandem or a solo canoe. Asymmetrical canoes typically have the widest section behind the centre of the boat, creating a longer bow. This configuration produces enhanced forward speed and tracking and is often seen in tour- ing and performance boat designs. Touring and per- formance boats will also have sharper, more knife- like tapers at the bow and stern to cut through the water efficiently. Whitewater and general-purpose boats will have blunter ends to add volume and give buoyancy in waves, providing a drier ride.


MATERIALS


Once you have chosen a canoe design that best suits your needs, your choice of material will be based on durability, cost, weight, aesthetics and the shape requirements of the canoe.


There are a staggering number of different mate- rials used to make canoes including: wood (sealed with canvas or fibreglass), polyethylene plastic, Royalex and composites (glass, Kevlar or carbon/graphite fibres mixed with adhesive resins). The most expensive boats are generally made of composites, Royalex or wood.


Strong, lightweight composites such as Kevlar are good for trippers, racers or anyone else willing to spend money to shave off pounds.


Heavier Royalex boats are favoured by whitewa- ter paddlers primarily concerned with bumping, bouncing, sliding and bending over rocks unscathed. Royalex, a supple vinyl-and-foam sand- wich that looks like plastic and bounces back to


shape when deformed, is also well-suited to the round, blunt shapes of most whitewater designs. Wood canoes—expensive once the craftsmanship is factored in—are in a class of their own. Though rel- atively fragile, maintenance-intensive and not excep- tionally lightweight, wood boats excel in beauty. They’re still popular because, to many people, canoe- ing is about aesthetics. Many paddlers are willing to give a little more care and take a little more weight for the timeless beauty and authenticity of a wood boat. Less expensive materials like fibreglass and poly- ethylene are used in a variety of boats for a wide range of purposes. In the simplest terms, these materials share the advantages of their higher-end cousins— the lightness of composites and durability of plastic. Finally, many manufacturers have their own ver- sions or combinations of these materials, proprietary constructions with trademarked names.


WHICH ONE SHOULD I BUY?


Whether you are altogether new to paddling, cross- ing over from kayaking, or a seasoned canoeist, you should determine your needs and desires before you wander into your local retailer or builder’s shop to buy a canoe. Be wary of the “a canoe is a canoe” sales pitch or the “does it all” model and be sure to test-paddle a boat before buying. It’s best to test- paddle a canoe under the conditions you will likely use the boat—outfitted, loaded with gear or on your most frequently travelled class of whitewater. When you’ve narrowed down your choice of


models, it’s the little things that may help you make up your mind. Some trim options, such as moulded, adjustable seats and sculpted yokes, affect the per- formance and handling of the boat. Others, such as wooden gunwales, wicker seats and cherry deck plates, serve the same functions as aluminum or vinyl alternatives, but affect the overall feel, increas- ing the boat’s intrinsic value.


Once you have determined your needs and matched a boat to those specifications, the ultimate decision comes down to two things: price and colour. —Canoeroots Editors


Rocker


Four Elements of Canoe Shape heavy


moderate straight


Hull Symmetry


asymmetrical symmetrical


straight shallow arch Seat Stern Deck Plate tumblehome flat 2005 Annual 31


The Canoe Map Sides flare Bottom round Moulded Yoke Thwart Gunwales


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