Sailing in Maine

Sailing in Buzzards Bay

Monday, October 27, 2008

Cutting out the Parts

Using the panel layouts from FreeShip, I marked the plywood with grid lines every six inches in the lengthwise direction. Measuring across these lines, I placed a wire brad in the wood at the edge of each plank location. Using a flexible piece of molding as a batten, I connected these points to create smooth curves that indicate the planking outlines.

This view shows the lower three planks (or strakes) in place. Notice that on the righthand side, between the clamp and the DeWalt box, I have taken the sharp front corner indicated on the original Hulls model and changed it into a smooth curve using the batten.

The lower edge of the first plank (right) was placed along the uncut edge of the plywood so that it will be perfectly straight. The cut edge of the plywood is on the left side.

The two 16' x 2' pieces of plywood were clamped together so that one cut will make parts for both sides of the canoe. I made a heavy pencil line so that I can see it through the sawdust when cutting.

I cut just outside the line so that the lines can be trued up later with a plane.

The doubled-up planks were mounted in a vice and planed down to the pencil lines. I planed the bevel needed between the planks at this time also, by adding an angle on the outside edges. When assembled, these outside edges will become the inside edges.

Some 3/8" (10 mm) plywood is marked with the bulkhead dimensions taken at the 48", 96", and 144" stations in the Hulls model. I then marked a cut line another 3/16" outside the first lines, to allow for the thickness of the Okoume plywood.

These parts will be used to make a basket mold in which the hull is assembled. By previous experience with the kayaks I built five years ago, this is the best way to get a true hull shape and tight fitting planks.

Two eight foot 2 x 4's were cut in half and the four foot sections were used to space the mold sections apart and hold them upright on the table.

Laying out the first three planks on the plywood took 2 1/2 hours. Cutting them out took another 1 1/2 hr. Laying out the basket mold, cutting, and assembling it took another 1 1/2 hr.

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