"He Wears Black and Has a Beard"

HMS Plywood: The Building

Toby Roworth

Sep 17, 2018

Since I saw a public boat ramp when I got slightly lost on the way to a viewing of my apartment, I've wanted to build a boat to take out of the lake. Of course this wasn't worth spending a lot of money on, so I aimed to build the whole thing out of a single sheet of plywood in a single day and pretty much succeeded.
Over the next couple of weeks I'll document the build and test of what my landlord christened the "HMS Plywood". But if you prefer, you can call it CrapBoat I.

The story starts with a few days I took off to get some rest after a recent install. Thursday was planned for general rest, buying materials and some more rest, on Friday I did the actual build and Saturday was the grand launch.
I'd already drawn some rough plans in a notebook, so knew I could make a boat about 2' wide and almost 6' long out of a single sheet of 8x4 ply. This size also fits well in the back of my truck, which was an important constraint, and would fit through all the doorways in my flat, something I only formally considered whilst doing this write-up.
So a trip to Lowes later I had just under $70 worth of boat-building supplies:
The expanding foam was very important to me, as it was a staple of Scrapheap Challenge's water tasks. This would usually be set of fire by the engine, resulting in sinking. Scrapheap Challenge sits up there with Robot Wars and Thunderbirds as a TV program that inspired me to do what I do now. It also had the honour of teaching me the Pythagorean Theorem, the explanation of which was slipped in when a team forgot to make a ramp the right length.

The main body of the boat was simple box construction, with the sheets of plywood attached to one another using the 2x2s. All joints were screwed and glued, and silicone applied behind any seams. I tried to avoid the glue and silicone beads touching, but probably wasn't entirely successful. The whole body of the boat only took about an hour to put together - this seemed far too easy.

Then came the prow...
The prow is made from three triangles, which made for lots of angles that needed calculating. Although I'd done some rough calculations on my notebook, I hadn't worked out what cuts I needed to perform - in fact, I went in not even knowing how I'd screw the triangles together.
After a lot of head-scratching, and a small amount of trig, I had enough worked out that I could get the sides on, and work out the bottom piece later. This meant cutting a 60° angle into a 2x3 (borrowed from the CrapWorkbench project) which is tricky without a table saw. In the end I clamped several off cuts to my circular saw to give the right spacing, which worked pretty well.

Once the sides were in, it was getting late in the day, so I was starting to get lazy. In the end the lower piece of the prow was screwed into two more pieces of 2x2 which were shaped mostly by eye, using a planer. The fit wasn't perfect, but good enough to get the job done.

The next morning I threw a quick seat together, and sanded a few of the edges down, ready for the launch...