Ultralight canoes and small boats are things of beauty, their apparent delicacy concealing great strength. They are lapstrake-constructed from marine plywood planks, each plank overlapping the one below it in a gracefully curved hull. Epoxy glue along the laps gives the hull structural reinforcement, minimizing the need for framing and permitting an amazingly light structure. Round-bilged and elegant, they are built over jigs, but the method is...