Hummingbird 16 Strip Planking Complete

I have made some decent progress on the build of my modified Adirondack Guideboat.

I started by using fir battens to set the shear line. Most advice suggested that you set your final shear line after planking. But I was pretty certain I could set a nice shear line using battens from the beginning. I knew from my drawing the height at each end, and at the mid point, and where the curve would center between fore and aft. And this way I did not waste any material.

The shear line looks weird in the super wide angle picture below, from a fish’s underwater viewpoint. But when sitting down, and viewing it from a waterline perspective it looks good to my eye. We will see when it gets flipped. I can always adjust it a bit with the gunnels.

The next choice was where to start running the strips from, from bottom board down, from shear line up, or somewhere in the middle? Again, different sources all have their opinions. I knew this was going to be a painted boat, no brightwork, so how the lines ran did not really matter. And it just seemed easiest to start at the shear, and work my way up. I thought I would end up having to put in lots of cheater strips, but the Paulownia wood was so flexible that ended up planking all the way to the bottom board that way. And the strips took it all in stride, with lots of curve, twist, and even reverse curve at the stems. Really nice to work with.

This was to be a quick and dirty build, so I used whatever staples, screws, tape, clamps or bungee cords I had on hand to hold the strips in place until the glue dried. I did not worry much about a perfect fit or alignment, or scarf imperfections. I did not bother with bead and cove on the strips. But I did hit some inside edges with a small plane in some of the curvier parts, for a tighter plank fit. It will all get faired with epoxy filler, and fiberglassed inside and out.

Next I pulled all the fasteners and trimmed all the excess along the bottom board and along the stems.

I also laminated some of the Paulownia boards together for what will become the final external stem pieces.

Next I will do quick fairing of high spots, and then will fill all cracks, holes, dents and low spots with thickened epoxy. And the new stems will be epoxied on. I am also going to laminate about 1/4″ of some really hard maple I have along the bow stems, and along a bit of each end of the bottom board.

Then the entire outside of the boat gets final longboard fairing, and then 4 ounces of S-Fiberglass in epoxy, doubled up on the bottom board to 8 ounces. Then more fairing before flipping and starting the process on the inside. Traditional guideboats also have bronze “shoes”, that protect the bow stem, and along each edge of the bottom board. I don’t want the weight of metal, nor any fastener holes. So I plan to run another 6 oz of fiberglass tape along the lower stems and the bottom board edges. That will give me 14 ounces of glass over impact/scratch zones, which should help protect this soft Paulownia wood.

For the gunnels I have some nice spruce to work with, leftovers from Schooner Martha‘s new spars (build story here). And for bulkheads and decks I have some 3mm Okoume marine grade plywood.

I am also starting to think about boat colors. I want it nice and bright and visible, because I plan to do some long distance adventuring in this craft where there will likely be other boat traffic. I will also be able to put up the mast, with or without the sail, with a navigation light on it. There will be another shorter mast on the stern bulkhead for a wide angle rowing mirror. I might also use the masts for a little tent to get out of the weather when I need a break, although I won’t be sleeping in this boat. My modified Skerry already feels too small for camping in.

And the sail plan is also changing after more research and thought. It will be a pure downwind sail. And it is now going to be more like a mix between a Dyson fan sail, a BSD Twins sail, and a Cape Falcon Canoe Rig. Since I first saw a picture of Dyson’s fan sail, probably 35 years ago, I have been enamored with its organic and beautiful appearance. Although the lack of forward visibility seems terrible. The BSD Twins sail is considered by many small boat sail experts to be a very good downwind sail for a small tippy boat, which is easily controlled. The Cape Falcon rig honestly makes the most sense, in terms of simplicity, and I will be copying the very fast way the entire rig can be dropped.

I am basically going to have the shape and boom/batten structure of the Cape Falcon (same as many kayak sails), but smaller, and double sided like the twins, on a carbon mast, and the sail made of spinnaker fabric. It won’t be as high as the BSD, but will have the self balancing feature. And like the BSD, I will be able to flip one side over the other, effectively reefing it by 50 percent. The mast and booms will be shorter than the Cape Falcon rig, but I will have enough height to be able to see under it. The entire rig, mast and all, will drop in seconds, without me having to leave my seat.

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