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1965 16' Sears Semi-V
Here is the boat, stripped down to aluminum. As you can see, the rear seat supports had been removed by the previous owner, and the seat replaced with an ungodly heavy wooden bench, made mostly of 2x4s and 1" ply. I could barely lift it out by myself once I figured out that it wasn't anchored to anything. The other bench seats were also made of either 2x4s, 1" ply, or both, and were very heavy as well and beginning to rot.
I planned very carefully. You can see here I measured the boat width at 6" increments to get a template for the front deck that would satisfy the curvature of the boat. I also planned how to build the storage hatches and measured for the rear deck and middle bench, which I decided to leave in for support.
I cut these out of cardboard using my calculated dimensions. They fit pretty well, but I was glad I made them as they did need to be trimmed slightly.
These cutouts, along with the front bench well, support the casting deck, and provide storage compartments.
and you can also see a preliminary fit of the rear floor.
with the storage cutouts visible. I sealed all the flooring and seating with fiberglass resin, for those of you worried that I used OSB instead of traditional ply. my reading, though, suggested that it was somewhat naturally resistant to water, and it was flatter than the other ply I saw at Home Depot. Nonetheless, I sealed it.
Yeah, I did this all without a flat surface in my backyard. I was impressed too.
I elected to leave the middle bench in and use it as storage/livewell since it was pretty clear that the benches provided significant structural integrity to the hull.
Here is how the boat layed out when I was done. The box you see on your left is a storage compartment with room for 12 3700 boxes plus numerous little odds and ends such as marker buoys, a scale, etc, etc.