At the front of the boat, the chine bends and twists as it goes around frame 4, the most forward frame, on its way to the stem as shown here in the middle of the picture.
The plywood planking must lay flush between the chine and the sheer, which is shown near the bottom of the picture. To lay flush, the plane formed by the chine must intersect the sheer or be slightly outside the sheer so it can be faired into alignment. The sheer must also be faired to have a flat surface in line with the chine. When they both line up the plywood will lie flat and everything is rosy. However, if the chine is not angled properly, you have a problem. The following picture from a fellow Malahini builder shows the issue.
As you can see from the strips of wood clamped to the chine, the plane is inside the sheer. There is no way to make them on the same plane unless you glue a shim on the chine to build it out and angle it toward the sheer.
I knew about this problem and the Glen-L book on boat building also mentions it. I was just not able to twist the chine sufficiently as I installed it to avoid this problem. So, I had to rip some wedge shaped strips of oak and glue them to the chine like so:
This is only glued to lower half of the chine because the top half has to faired quite sharply toward the stem. Once the glue sets, I can grind the end of the shim to a smooth taper and proceed with fairing the chine to accept the plywood. Believe me, boat building to plans is not an exact science. The plans get you in the ball park, but due to the vagaries of wood and your technique, each boat made from the same plan will be a different and unique creation.
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