IT STARTS HERE
Evolution and Design
How do you design a fast canoe? It’s not a simple question. Hydrodynamics may have crossed from art to science a century ago, but it’s application to an ever changing ocean environment is not so black and white. The reality is that ‘optimal’ hull shapes don’t deliver great performance without adaptations. Design concepts have to be proven in the real world.
To build fast canoes, we design, prototype, and test. Then do it again and again. Good design is part theory and part evolution. We design our canoes using a mathematical model that allow us to generate new, fair, hull shapes by changing only one aspect of an existing design. When our testing uncovers weaknesses in the design, we can change only the relevant aspects of the design.
The parametric hull model is then imported into a CAD program. The model is surfaced, and the deck is designed. From the 3-D CAD model we machine molds to build an accurate prototype. It’s a time consuming process, but it’s the only way that we’ve found to make a lightweight prototype to test the design.
The Storm is the first outrigger canoe to be molded in one piece, simultaneously eliminating excess weight and creating a stronger canoe. The construction is revolutionary, Every new design we make will feature this construction, we’re never going back. The Ehukai, Vortex, Malolo, and the new Antares are now built this way, as well as most of our ama’s. Don’t confuse the weight with the structural integrity – these are the strongest canoes we have ever built, even though they feel impossibly light.
The Right Stuff
Building a great canoe starts with selecting the best materials. Carbon fiber is amazing stuff, it’s light, strong, and easily molded. We use lots of it in our canoes – more in fact than any other canoe on the market. We use primarily unidirectional (UD) carbon. Woven carbon fiber looks great, but because the fibers are crimped stresses are carried by the epoxy first. Laminates made from UD carbon are simply stiffer.
Carbon fiber prepregs are used for composite structures in aerospace and other advanced industries. The fiber is machine impregnated with high temperature curing epoxy resin. The resin to carbon ratio is tightly controlled resulting in the lightest and strongest laminate possible. This material is the so important to us that we located our factory in the heart of prepreg manufacturing in China to ensure the best supply possible. There are several state of the art facilities in our area. This allows us to work with these suppliers to tailor the prepreg to our requirements.
Epoxy resin is what locks the fibers together, but not all epoxies are the same. Epoxy formulations used for room temperature and low temperature oven curing can have surprisingly low service temperatures. When the laminates heat up in the sun the epoxy softens, and the laminate distorts. Woven carbon and glass will ‘print’ giving a textured pattern to the canoe. Epoxies formulated for hand lamination often contain diluents to reduce the viscosity of the resin which weaken the laminate. The epoxy used in prepreg has a higher molecular weight, contains no diluents, and has a very high service temperature. The result is a tougher canoe that doesn’t print.
What’s in you’re sandwich? Only a handful of core materials can stand up to the heat and pressure of the autoclave. If a core can take 60 psi at 250 fahrenheit, it’ll fare well at the beach. Though we use a variety of core materials, Corecell is what we use most often.
Creating a fair hullshape in a CAD model is only half the battle. In order to take the design from the digital world into the real world you need CAD’s big brother CAM. Our factory is equipped with a full array of CNC equipment.
Our eight meter (26′) long, 3.5-axis, CNC router was designed by Mike Giblin and built for the sole purpose of milling precise canoe masters. This machine is accurate to within a few thousandths of an inch. Additionally we built a 15 meter (49′) long, 5-axis CNC router to build our OC6 masters.
For making steel tooling for components like rudders and iakos, and for production work we have 2 machining centers. For milling seats and components we have two smaller CNC routers. For plotting prepregs and fabrics we have an 18 meter (60′) long CNC plotter. For hard to cut materials like hardened tool steel, or for difficult to machine geometries we employ an EDM machine. FYI, we have a Co2 laser, were talking laser beams people.
At the heart of our canoe molding department are the autoclaves, also designed to our specifications. Our 8 and 15 meter long autoclaves are pressurized curing ovens. The autoclave allows us to accurately control time, temperature, pressure and vacuum profiles of the curing cycle. Autoclave cured prepregs are the state of the art in composites manufacturing. The autoclave is where Formula 1 teams and defense contractors go when they need the highest quality carbon fiber components possible. The canoes are laid up in temperature controlled cleanrooms. They are then vacuum-bagged and cured in the autoclave at a high temperature and pressure. The result is a ligher and stronger canoe than is possible with ordinary wet layup vacuum bagging.