Sunday, August 24, 2008

Inwale Assembly...Near Disaster!

Once the carved inwales had thoroughly soaked in the lake a few days, it was time to lash them with temporary thwarts to form the inwale assembly. This involved first lashing the ends with soaked spruce roots. I read somewhere that notching the tips would allow the first coil of root to stay in position, so two grooves were cut lightly into the cedar. The ends were temporarily held together with a trigger clamp while being tightly lashing with root. When both ends had been lashed, the inwales began to take their shape.

Cut notches; Binding with wet root; Ends lashed

To put in the centre thwart, the inwales were soaked with boiling water and very carefully stretched apart so that the temporary thwart could be inserted. I needed to push down with my foot and lift with both arms to get the inwale to tightly stretch in this manner. Here's the shot right when the thwart slipped into position and I stepped off with relief.

Stretching apart the inwales for the centre thwart

Feeling confident that the temporary centre thwart was in and there was no signs of cracking, I lashed it into position with some nylon cord and moved onto the intermediate thwart and end thwarts. I had successfully tied in the other thwarts and was working on one final end-thwart when disaster struck! The tips at this end cracked (right where I had notched the cedar)...DOH! With the other end already lashed up, I didn't want to lose the work so far, so I temporarily clamped the broken end and pondered a solution.

Broken Gunwale tip....CRAP!

I figured it could be salvaged by binding right below the crack point while losing only about 2 inches from the original tips. Trouble was the inwales were already under tension from the other lashed end and the clamp would only grip right at the ends where the "repair surgery" needed to take place. I ended up working with one hand on the clamp precariously gripping the inwales in place while frantically shaping the broken inwale with my recently made mini crooked knife. Then with a 1/16th drill bit, I bore 3 parallel holes through both inwales. These were then stitched with strong, waxed linen thread used for leathercraft in a sort of figure 8 pattern. Over this secured end, I further lashed it with spruce root. It turned out amateurish but is holding nice and strong. At anyrate, the inwale tips will be covered by a bark deck piece in the end so no one will know this fudge repair job is there but me and all of you reading this.

Repair with waxed cord; Spruce root lashing on top

Of course, the side with the broken tip is now 2 inches shorter and this affected the width of the inwales at the intermediate thwart (it is now slightly wider than before). This means that the inwales are not perfectly symmetrical, but have a slightly narrower, sharper profile on one end (bow) and slightly wider curve on the other (stern). I don't think this will mess things up because this is the same shape in most asymmetrical hulls today. And since my canoe will need to be stitched from various panels rather than a one-piece hull, it'll have an obvious bow and stern based on which direction the lap joints face. So basically, this boat will feel wrong if it is paddled in the wrong direction, but I can live with that.

Symmetrical Hull; Asymmetrical Hull

Following some practical advice from expert bark canoe builder Ferdy Goode (whom I met at the WCHA assembly a few weeks back), I decided to prebend the inwales since they had been thoroughly soaking in the lake for a while. With some extra boiling water, some rocks, and 4x4 frames from another project, I propped up the ends and weighted down the center of the inwale assembly. My intended design has relatively lower ends with a very modest sheer line difference of about 4 inches from tip to center. So this setup worked out. I was also cautious given the day's earlier breakage so didn't want to push my luck with unnecessary bending

Tips elevated 4 inches; Weighted down for pre-bending

Now they're just waiting to dry out so they can be lashed onto the canoe.

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