Choosing Materials for an Outrigger Canoe

Choosing suitable timber for your boatbuilding project is important and can be difficult depending upon your location. Cedar-strip planks can be ordered already prepared with cove-and-bead edges, but most builders will choose to save money and cut their own. Western red cedar is the first choice for strip-planking because of its light weight, color, and rot resistance, but many other species are also appropriate. Spruce, pine, other types of cedar, redwood, paulownia, or cypress are a few others that have been used successfully. Planking timber is ideally very lightweight, dry, straight-grained and available in long, clear lengths. If you cannot find suitable timber in your local area, check through boating or boat-building magazines for companies that will supply it.

Timber for gunwales stems and chines is ideally harder and heavier than cedar because it has to hold fasteners well and be exposed to more abuse during use. Laminated cross beams can use cedar in the inner layers, with a harder wood like fir or mahogany on the top and bottom.

Plywood can present you with just as difficult a choice unless you have a healthy budget and purchase the most expensive marine grades. BS1088 is a Lloyds standard for marine plywood that ensures mainly the quality of the veneers in all layers. Marine and exterior grades of plywood use the same waterproof adhesive. With the marine grade, you are mostly paying for the quality of the inner layers. If you wish to use plywood of unknown quality, take a sample and expose it to repeated cycles of boiling and baking in an oven.

If you are using ply with one good side and one lesser-grade side, put the knotty side out and glass over it, leaving the better side on the interior of the hull. One-fourth-inch (6mm) plywood is available with three or five plies; the five-ply is far superior. Check the dimensions of plywood sheets, as some are metric sizes and some are imperial (i.e., inch) sizes.

Screws, nails, and bolts are ideally made of anon-corrosive metal like silicon bronze or stainless steel. You can use galvanized steel fasteners if they will be fiberglassed over.