After turning the boat over, back to upside down, it was time to give attention to the final shape of the bottom. The first task was to close in the back holes where I had extended the stern sides to fix the front-to-back balance problem. It was more fully described in the post Roadblocks.
I needed to add hull plank pieces to join the ones that were cut off at the previous end of the stern.
The first bit of preparation was cutting an angle on the existing hull shell to spread the adhesive over a larger area and strengthen the future joint. I used a 1:8 ratio, cutting a 4″ scarf on the 1/2″ piece of marine plywood. The best way I could figure out was to make an angle jig for my router, which produced a fairly consistent surface as I moved it up the line.
The replacement pieces were not very large, but difficult because apart from the parallel sides, no other angle was square. I first cut the plank to width, and then took it to the bandsaw to free hand a rough angle cut. This is not so safe, but works out well if you hold the piece steady and don’t change the angle much.
This cut defined the end that would fit against the existing hull, so then I took it to the jointer to cut the 1:8 ratio scarf. This could be done with a hand plane, a belt sander, or router but I decided to experiment with the jointer, for its precision. This is definitely dangerous.
It must be done patiently, a small angle at a time until the full angle is cut. After a few trial cuts, my extended finger eventually gave the right finishing angle.
Then, it is back to the hull, to see if the end angle still fits and the scarf angle conforms to the previous router cut area. I checked with a metal ruler to see if it was the same height as well.
When this was all done, I added the tongue and groove to the sides to make each piece join to the next in the strongest way. It also contributes to making sure the neighboring pieces are level to the next one.
After that piece was done and temporarily screwed in place, the same process was repeated to finish the ten needed to fill the hole. When they were epoxied to the hull, they became just as strong as any other part of the surface, and will be invisible to inspection shortly.
By now, they are already covered with the next layer, and will never be seen again. Still, I enjoy putting my best effort into each piece, so that the boat has a good chance of functioning well and lasting a long time.
It is satisfying to imitate the Master builder who put us together in our mother’s womb, and knows the smallest details of our lives. As Eric Lidddel said in Chariots of Fire, “I believe God made me for a purpose, but he also made me fast. And when I run I feel His pleasure.”