The QuickLap Canoe

Lapstrake boats are to many people the prettiest boats on the water. The shadow lines formed by their overlapping planks highlight the contours of the hull, leading the eye to follow it's shape. They have a reputation, however, of being difficult for an amateur to build. A builder must first accurately cut a series of molds, spaced at regular intervals on a strongback, to define the hull's shape. Wooden strips, or ribbands, are then fastened to the molds to outline the shapes of the planks in a process called lining off. All of the pieces made to this point help to define the hull's shape, but do not become part of the finished boat. If multiple boats are going to be built to the same design, the time spent constructing the building jig can be economically divided among all the boats; if only one is being built, jig construction becomes a substantial part of the building time.
When I first started exploring the possibilities of computer cutting boat parts I really wanted to try building lapstrake boats. Only after a lot of experimenting did it occur to me that a lapstrake hull could be built like a stitch and glue hull, with one half of the lap added to each plank's width. This "slipped" stitch-and-glue method required a flexible "rivet" so that the planks could bend to a natural shape. Plastic cable ties inserted through paired holes in the plank edges, with cable ties slipped over their ends, were just the thing. Using this method, the shape of the planks define the hull's final shape, not molds or frames. After the hull is riveted together, the overlaps are filled with an epoxy mixture, locking the shape and creating a lengthwise "stringer" at each lap.
Designing for the " QuickLap" method was much more difficult than I had imagined. Since this method allows the hull to take on it's own natural shape, the shape that was drawn on the computer screen was not always the shape of the finished hull. After many hours at the computer and several prototypes I had a design for an 11' double-paddle canoe that I was happy with, loosely based on Henry Rushton's Wee Lassie. This 13'6" QuickLap canoe evolved from that first canoe.
[ Next ]