Scratchbuilding a Wood Strip Sea Kayak
By: Jason Bowling
Tags: Projects, Outdoors, DIY, Boats, Makers

I wanted a sea kayak badly to go camping with, because they go fast and can carry enough cargo for a week in the wilderness. I’d just come out of a divorce, and didn’t have enough money to buy one. I had some simple woodworking tools in a 16'x12' (4.9m x 3.7m) shed with a single 15A circuit. If I turned on a belt sander, the lights dimmed. I knew some people had built them in their living rooms, so I figured I had no excuse. I knew it would take a few hundred hours of work, but I had more time than money. I wasn’t entirely positive I could do it.

After some research, I settled on Bryan Hansel’s plans for his Siskiwit Bay 17 foot (5.2 m) strip built kayak. Bryan is a great guy — a writer, photographer and adventurer, and he was doing the sorts of travel I was dreaming about. He had pictures of the boat out in the waters of the Great Lakes. It was stunning. I wanted one.

I ordered a copy of Nick Schade’s book on building strip boats, which is outstanding. It filled in the gaps from the online build logs for similar boats that I had found.

I only have very basic woodworking skills and tools — I can run a table saw, make some basic cuts with a jig saw, nothing really complex. What I learned was that building a boat like this doesn’t require a tremendous amount of skill. It requires doing the same basic processes, over and over, for a long time. If you screw it up, you cut it out, sand it down, and do it again. It demands patience and time, but not any particular precision.

The plans mostly consist of printable cross sections of the hull at known distances from one end. The first step was to print them out full sized on paper, cut out plywood forms that match the shape, and attach them to a temporary spine made out of a couple of pine 2x4 boards joined end to end. This whole assembly is a jig used to set the shape of the hull, so it needs to be pretty carefully aligned. If your spine is warped, your hull is warped, which will result in it pulling to one side when you paddle.

You might recall that my shop is 16 feet (4.9m) long, while the boat I was trying to build was 17 feet (5.2m) long. I ran the math before I bought the materials for the spine, and determined it would just barely fit on the diagonal with the door closed. With the spine up on saw horses, I could cross under the boat to change sides, which I did a whole lot of times.

I was younger then.

The plywood forms on the spine

The edges of the forms get covered in duct tape to make sure the hull and deck don’t get glued to them later on.

Because I was more concerned with cost and durability than with super light weight, I chose to do the hull in pine, and the deck in cedar. I knew I was going to paddle on both lakes and rivers, and I wanted it to be pretty close to bulletproof.

It took visits to three hardware stores to find the lumber I needed — straight, free of cracks and knots. I didn’t own a table saw, so I used a circular saw flipped upside down and bolted to a table with a notch to pass the blade, like an old school sawmill. I can’t recommend this, because it is completely devoid of any of the modern safety devices that make a table saw reasonably safe to use. It has long since been dismantled, but it did the job . The 3/4" (1.9 cm) boards were cut into strips a bit over 1/4" (.64 cm) thick.

Once the pile of strips was cut, I laid the shear strips — the strips that make up the uppermost strip of the hull. The strips were stapled to the form with construction staples.

The shear strips are installed, and are the guides for all future strips

From here, building the hull was simple, if a bit tedious. Each pair of strips was spliced to the needed length, trimmed along the edge so that it would snugly fit, glued to its neighbor with basic wood glue, and stapled to the forms to hold the shape. The bow and stern formed where the strips from each side came together, and the gaps filled with custom whittled plugs of wood. In this way, the hull slowly took shape. It was, at this point, quite rough on the inside and outside.

Once the hull was fully stripped, I flipped the boat and built the deck the same way. A hole was cut for the cockpit, where the paddler would sit.

With the deck and hull built, I had a collection of rough strips attached to the form and glued to each other, but the surface was very uneven.

I called my dad, and we spent a happy morning with a wood hand planer shaping the exterior of the hull and deck. Paraphrasing an old wood carving joke, we just removed everything that didn’t look like a boat.

After planing and shaping

I spent many additional hours with a palm sander, starting with coarse sandpaper and eventually getting to very fine grit. The goal was to make it smooth both visually and to the touch — any flaws would be forever on display under the epoxy and fiberglass that was to come. I sanded until I was happy — there were many remaining flaws, but I was building a boat for travel, not furniture.

At this stage, the hull and deck was smooth, but quite fragile. They were still stapled to the form. What gives a completed wood boat both beauty and tremendous strength is the combination of a wood core, layers of marine fiberglass, and marine epoxy.