Design concepts for selecting the right boat by Michael Lampman
There is an axiom: “The pleasure one gets from a boat is inversely proportional to its size”. After years of devoting more time and money to maintaining boats than to using them, this simple truth became self-evident to me. Canoes and touring kayaks are versatile, small, simple and easy to haul around. They require far less maintenance than other boats and can usually be stored without taking up space that might be devoted to other purposes. I use my kayaks and canoes far more often than any of the the other boats I have owned over the years.
In selecting paddlecraft, it is important to keep such matters in mind because there are many models on the market that defeat these advantages. Many are just too heavy. More than a few are so difficult to paddle that the fun goes out of using them. Still others are burdened by complex gimmicks that can be maintenance nightmares and some are just plain uncomfortable. This three part article will examine the qualities to be considered in selecting flatwater canoes and touring kayaks, (the requirements of whitewater boats are very different). Part one is concerned with materials. Part two will focus on basic design characteristics and their impact on performance and the third part will be about features and accessories such as skegs, rudders, and paddles.
Part I: Materials
A corollary to the above axiom is, “The pleasure one gets from a canoe or kayak is inversely proportional to its weight." Recently I attended a conference in South Florida and took an opportunity to go paddling. I had to carry a rented fiberglass kayak down a steep rocky bank to a tiny beach near my hotel. The paddle was delightful but my paddling was curtailed for several months afterward because of the hernia I contracted lifting this 60 pound boat. Last summer my wife and I took a paddling vacation trip to Maine. The plan had been to drive and cartop our kayaks but we came up short of time and had to fly instead. We rented a fiberglass tandem kayak for the week transporting it on a rental car. This boat performed admirably in the seas of coastal Maine but it was incredibly heavy and all but unmanageable. Our backs told us that if we owned such a boat we would rarely paddle it.
Thus, the most important characteristic of a material may be weight. If your boat is light enough to be effortlessly tossed on top of the car, you will use it regularly. If its a painful struggle you probably won’t. A second important quality is the design limitations of a material and consequent effects on performance. A third is durability, maintenance and repair and finally there is the subjective value of beauty.
The materials of which modern canoes and touring kayaks are most often made are plastic, sprayed fiberglass, hand laid fiberglass, plywood, wood strip composite, kevlar, and carbon fiber.
1. Plastics. Thermoplastics are the cheapest materials of which paddlecraft are built. The mass production process is also cheap making plastic boats less expensive than others by a very wide margin. Although not inherently heavier than other materials, plastics cannot be used in the same way. To perform well a boat must be “stiff”. This means that the hull should retain its shape against the pressure of water. Plastic is flexible and subject to “tin canning” under pressure. To make a plastic boat reasonably stiff requires added thickness or internal structure so that the total weight is often excessive. A reasonably stiff single plastic touring kayak weighs up to 65 pounds. Moreover, because the whole boat bends and twists, bulkheads and skeg trunks twist loose and eventually leak. It is a myth that plastic is the most durable and lowest maintenance material for a boat. Sunlight degrades it more rapidly than other materials and a plastic boat left in the hot sun at your campsite or on top of your car will literally melt into a new shape in only minutes. Some plastics have better “memory” than others, returning more easily to their original form after heat distortion. If a canoe or kayak is used at all it will be dragged across gravel, scraped on concrete boat ramps, or run aground on oyster beds. The scratches and gouges of normal use are all but unrepairable in plastic. In addition it is difficult to attach anything to plastic making outfitting and accessorizing harder. If budget is your main consideration the compromises associated with plastic may be acceptable but bear in mind that you get only what you pay for.
2. Sprayed fiberglass. In this fairly inexpensive process short glass fibers are mixed up with polyester resin and the resulting goop is sprayed onto a mold with a tool called a “chopper gun”. This makes a very stiff hull that can have the same beautiful finish coat as hand laid fiberglass but it is brittle and not very strong. A fall onto a concrete driveway is apt to crack the whole thing open like an egg. To compensate, such boats are often as heavy as plastic ones. Few kayaks are built this way but canoes often are.
3. Hand laid fiberglass. Hand laid glass is woven fabric layered and soaked in polyester or epoxy resin. It is very stiff, very strong and moderate in weight. Finished fiberglass can be smooth and beautiful. Like most materials, the finish must be protected from excessive exposure to ultraviolet but otherwise it is very low maintenance. Because the gelcoat, (finish layer), is relatively thin, scrapes and scratches are usually quite visible but can be repaired at reasonable cost. This method of construction is somewhat labor intensive so these boats are significantly more expensive than sprayed fiberglass or plastic.
4. Plywood. Plywood boats are more often sold as kits for home builders than as finished boats. They are quite stiff, very light and very attractive. Although plywood forms the core of the material it is usually sealed in epoxy resin and woven fiberglass giving it the same low maintenance characteristics as hand laid fiberglass. Because plywood bends well in only one direction, and because it is somewhat flexible, these boats have “hard chines”. They are made up of several narrow, flat panels meeting at a hard angle, (chine), rather than having a rounded bilge. Repairs to minor damage are easy although deep scratches remain unsightly because the finish layer of the plywood is very thin. For anyone comfortable in a wood shop this is a wonderful way to have a beautiful, fine performing kayak for a very small price.
5. Wood strip composite. “Strippers” are built by laying many very narrow strips of solid wood, (usually cedar), over a mold. The strips fit together with “bead and cove” joints, the boatbuilder’s equivalent of tongue and grove. The wood is saturated with epoxy resin and layers of tightly woven fiberglass are embedded in resin on both sides. The result is a composite material that has nearly ideal stiffness, a very high strength to weight ratio and resilience unmatched by any other material except traditional wood. While the hull is stiff against the pressure of water, it yields instead of breaking under impact like slamming against rocks. The visual impression is of a round bilged wood boat resembling the classic cedar canoes of an earlier era. Strippers are extremely light and strong and are as easy to maintain as fiberglass. They are the easiest of any to repair and normal scratches tend to hide naturally. They can be unmatched for beauty and performance but construction is labor intensive so they are not inexpensive.
6. Kevlar. Kevlar is a high tech fabric laid in much the same manner as woven fiberglass and saturated with resins. It is the stiffest of all canoe and kayak materials and one of the strongest, most durable and most abrasion resistant. It is extremely light. Kevlar boats are quite expensive but well worth the investment.
7. Carbon Fiber. The lightest material of all. It is also very stiff. The cost of the raw material is so high that it is used most often for building serious competitive racing boats where a few ounces are worth hundreds or even thousands of dollars. Some boats are built using a combination of Kevlar and Carbon.
Michael Lampman is a designer/builder of cedar strip canoes and kayaks; owner of Solitaire Boats, LLC. He is the founder of Paddletally (http://www.paddletally.org/) a large and active paddling club in the Florida Panhandle where he and his family have been paddling for 25 years. His line of boats can be also be seen at http://solitaireboats.com