Model building

Planking continues from the bottom up: the other garboard, the middle planks and the sheer planks.

A difficulty I discovered was in fitting and trimming. The planks are slippery, especially at the lapped faying surface. They are hard to hold in place steadily enough for accurate marking. The solution (and why didn’t I take a picture?) was to temporarily attach a batten to the lower plank, right at the lap. Then, the next plank can be rested against the batten and marked.

As before, masking tape makes the best clamps.

You can see “the gains” at the far right end of the mid plank photo. The overlap gradually becomes an edge-join before reaching the stem.

Once all the planks are attached, we can remove the boat from the building horse and then trim the sheer plank down to the edge of the clamp. More fun with my favorite plane.

By the way, attaching the model’s planks with glue is much easier than clinching with tacks as I will do for the 1:1 version. Copper tacks, 3/4 of an inch long, are pressed through the overlapped joint. As they are hammered in, a curve shaped iron is held inside the boat. The point of the tack strikes the iron and is turned back on itself, making a j-shaped fastener that holds tight. There are only a few hundred tacks needed on thie size boat.

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The garboard plank is the lowest plank on a boat or ship, and the first to be placed on this boat. Like most other parts, I temporarily glue a part of the drawing to the lumber and shape it, loosely, to the drawing. Leave lots of extra when doing the first cut for planks, especially on the upper edge. Here, I trimmed very close to the bottom.

That’s a simple little modeler’s vice, set sideways on a fixture, making it easy to see the lines.

The upper edge of the plank is found by trial fitting. The markers for this edge are the apex points on the bulkheads and frame. Trim until it fits. We also need to cut “gains” before hanging the plank.

The planks on this boat are “lapstrake,” literally meaning the strakes (old term for planks) overLAP each other. At the ends of the boat, the overlap diminishes with the planks coming to a smooth join with the stems. This transition is accomplished by fitting “gains,” the area where the overlap transforms into an edge-to-edge join. There are two methods for cutting gains. One method, called “shiplap,” cuts an angled half lap in each plank. The other, called “dory lap,” bevels the edge of each plank. Because of the thinness of these planks, I used dory laps.

Through a good bit of experimentation, I found that the best way to hold the planks in position while glue sets is with thin strips of masking tape and a couple of de-toothed alligator clips. Fastening on the 1:1 boat uses very small screws and clinched tacks. We use only glue on the model.

The garboards are not only the widest planks, but the ones that take the most twists and turns. They are plumb vertical on the ends, and nearly at 30 degrees in the middle. Fitting this plank is usually the toughest part of planking any boat.

By the way, you can see two simulated screws in the bottom of the stem in this photo. They are actually bamboo trennels that add strength, and this will be the last time they are visible. Paint covers them later.

The keen observer will see that the “clamps” are in place. These are the very thin strips set into the top of the bulkheads and the frame. The fit into notches in those parts and form the line and structural support for the top, or sheer, of the uppermost plank.

These planks are of aspen and are a mere 5/16 inch thick, or only 20 thousands of an inch thick at 1:16 scale. I have a stunning window just beyond my modeling workbench, and the afternoon light shown through, showing the translucent thinness of the planks.

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With the stems properly positioned, it is easy to attach the bottom. It has a little bit of rocker and needs a few weights to hold it in place. It’s ironic that I have so many squares. Very few things in boats are either square or straight. So, this is what they’re good for. The 1:1 version uses screws for fastening. Screw fastenings were yet another reason to build up the bulkheads from solid wood, even if it was thin.

The bottom is cut oversize so that it can be trimmed to exact size once it is affixed to the frames. But, how to mark? Marking where the frame meets the bottom id easily done, but to the wrong side of the board. How can we reliably get that mark to the side where we can use it? A very nice little marking tool does the job. Lay it against a frame or bulkhead and mark the extension on the bottom.

Mark three places along the side. We then have five points defining the bottom’s shape, the 3 marks and the points of the stems at each end. Fair those marks with a batten. Be generous with bending or bowing the batten. Keep the line smooth.

Then comes the fun with my favorite small tool. This is a small bronze luthier plane. available from Lee Valley tools. It is a jewel of a plane, simply wonderful to use. We will use it quite a bit in building this boat.

The bottom is planed to the line, including setting a bevel on the edge that matches that of the bulkheads and the frame. Then, the edges of the bulkheads are given a bevel that matches the fore and aft curve defined by the bottom.

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