Tamboura Build

I built this canoe a few years ago. It is a Skin on Frame concept I call Cane on Frame, built with 100% natural materials. Any people group on the globe could have made this same canoe with the technology they had 4000yrs ago. I intended to build a few more all natural canoes of slightly differing construction styles, then write a book documenting the difficulties of satisfying the modern consumer with any product even remotely sustainable. I am not sure that plan will blossom, so I’ll publish this boat build in this manner.

I can start a few years further back, with my first canoe build. It was cardboard mache, sealed with a skin of what I call WaxLac: a 50/50 mix of beeswax and shellac. That whole boat was my own concept: I created the hull shape from semi-scratch. I plotted out the midship forms from four different canoes who’s plans were included in books so I could get the beginnings of an idea what canoes are supposed to be shaped like, then blended them towards handling attributes I personally feel are valuable.

I took that midsection, and drew out a set of sections.

“There is no one perfect canoe.” That is a truism tossed around a lot. And it is correct to a point. But there can be one perfect canoe per person.

This is supposed to be a thread about a build, not a treatise on design principals. So I’ll keep this as short as possible by saying...

Flat sheer is wonderful for windage and I like the look, but not so great in waves. So I increased the bouyancy of the ends to rise with waves (which is OK because the boat is short), but blunt entry and exit will slow her down some. I kept this shape short for creeks, which left me ability to keep rocker flatter for more cargo capacity and help her head straight, but short will slow her down some. To pick some of that speed back up (or, how about we call it 'effortlessness in paddling across lakes or up-crick?’) I rounded the heck out of her bottom. More than that: I V'ed her bottom, to deflect creek sticks and rocks. Which means she is a TIPPYcanoe.

I want to be part of this canoe, at all times immediately and intuitively aware with all my senses of her precise positioning in to relation the water, so tender to me is not a drawback. Very few others will want this canoe. But I do. 

I made a massively mongo boxed strongback. Pretty tough to make anything more accurate than it’s foundation and this is to be used on many future canoes, so not only needs to be true, it needs to last true. There are no flat areas in my house or garage even three feet in any direction let alone 14, so I began with a boxed platform to build the strongback on.

That bottom box has come in enormously handy since. When you’re working on long skinny projects made up of lots of long even skinnier parts, a long skinny workbench (with an included tool shelf) you don’t mind using as a sacrificial block for drilling holes, support for sawcuts, etc, comes in useful a lot. Even as a soaker box for gunnels, holding soft Cedar off a concrete floor, or clamping sheets of plywood to for ripping into boards with a skilsaw.

I recommend one.

Thar she glow, bright white.

The canoe this thread about is named Tamboura. Feminine form of Tambourine Man. "Take me on a trip upon your magic swirling ship.” I intended this all natural boat to connect me to Nature as intently as if I were on mushrooms.

All wood that went into the canoe this thread addresses was storm-downed. Not something I insisted on or even initially considered, but the cards did fall that way and I am pleased. More importantly to me it’s all great stuff. Great big fat oooold growth walnut, and great long streaks of Ash.

Tamboura’s keelson is doubled, a twin beam in suspension. The concept is inspired by her heritage: the low weight rigidity created by the trestle structure, same as a birchbark canoe achieves with gunnels pressed outwards by the thwarts. I decided I’d mirror the same on the bottom. 

And a closer view of the spreader sticks and their lashings...

The extreme ends of the Trestle Keelson, to ensure they did not drift but maintained the inline line of Tamboura's attention due ahead, were linked with a Walnut stopwater.

I think that’s what they’re called, even in this application. I don’t actually have an official education in this stuff. 

Tamboura does not have breasthooks as such. But rather two great big three way socket joints on the tippy corner of each end. The shape is critical, to hold the gunnels at proper angle. And so is the strength. It took a walnut tree 48in in diameter to provide perfect grain orientation in all directions. Since wood obtains it’s strength along its grain stripes, and here we are linking one gunnel to the other at an angle, I wanted the sweep of grain to meet the gunnels as perpendicularly as possible. So the wide part of the wedge went to the outside of the tree.  With the tip out of the pith or even tight circled grain, and the flare not yet to the sapwood.

Initial angles were machined with a table saw, then I taped off areas for the surfaces a table and fence could no longer guide, to guide a belt sander.