The kayak is a 'Ravenswood' fuselage-frame SOF design by S. Jeff Horton of Kudzu Craft Skin Boats in Alabama. (www.kudzucraft.com)
It's 15' long, 24" wide.
Frames are 12mm Hoop pine plywood, and the stringers are scarfed Western red cedar. Framing timbers are waterproofed with tung oil.
It's lashed with artificial sinew and skinned with 9oz polyester, shrunk over the frame with an iron and doped waterproof with Aquacote clear water-based polyurethane.
The only glue I needed was to scarf the stringers (I used Titebond III) and the only screw fixings are in the coaming (clamping the coaming onto the skin) or securing the footrests and deck lines to the frame.
I chose skin-on-frame construction because I felt it had some great advantages:
- No epoxy and epoxy dust around the house and kids,
- Light weight (I think the kayak weighs around 8-10kg all-up),
- Relatively fast to build (although it still took me >12 months),
- Easy to build in a confined space (our front porch is pretty narrow).
The Ravenswood design seemed right for me because it combined reasonably short length overall (17' would have been hard to store at our house) with plenty of volume & reasonable stability (many alternative designs were considerably narrower - set up for lean, trim Inuit types). It's optimised for around 3-4.5 mph which seemed realistic for me.
I cut out the frame profiles from the plans, stuck them to the plywood with spray adhesive and cut them out with a hand jigsaw and pencil-rounded them with a bastard file and sandpaper.
Then I set up a clamshell strongback over sawhorses on our front porch, cut out some ply brackets and set out with stringline and spirit level.
The frames were clamped to the brackets, and the stringers temporarily held to the frames with occy straps. Once everything was straight and level I lashed the stringers to the frame with the artificial sinew. The wax in the sinew grips hard, and the lashings could be pulled very tight. I shaped the stringers to fit the plywood stem and stern pieces, lashed them together then oiled the frame.
Once the frame was complete and off the strongback I wrapped it in the polyester fabric and sewed a rolling seam along the deck centreline. (The coaming sandwiches the edge of the fabric around the cockpit.) I tightened the skin to drum-tight with an iron and doped the skin watertight with 2-part water based polyurethane (I wanted a clear finish to get that fantastic translucent look - it looks great with the sun shining through the kayak).
Getting the sewing holes in the seam watertight was tricky, and I used some polyester marine sealant goop to fill them.
It's a great kayak. It's light and easy to carry to the water and feels fast, stable and manoeuvrable – just ask Josie!