Building The Hull
 

 

 

 

 

 

 

                                                                                                    Feb - Sept. 2005

 

In the winter months of 2005, the internal bulkheads and temporary moulds were built. First the entire hull was lofted onto the wooden floor at full scale (actually the plywood sub-floor serves two purposes: it insulates the concrete floor and makes it much more comfortable to walk on during the harsh Canadian winter. I also painted the floor off-white to use it for lofting). The moulds were then lofted onto Mylar sheets, which were then laid over the wood to draw the outlines. The forms were then finally cut to size. In the case of the permanent bulkheads, they are 1/2" marine plywood that received 2 coats of epoxy after they were cut. Epoxy was done while they were nicely lying flat on the ground. The temporary moulds were built of particle boards which would be discarded after the hull is done.

The frame supporting the moulds was built on a strong-back with 6 casters. My garage is very tight for the Chebacco and the hull would need to be moved around to accommodate building different sections. The height and alignment of the moulds were checked and triple checked against the lofting - this was the defining moment of the hull shape and there's no room for error.

The massive keelson backbone is built of solid Douglas fir. I bought a pile of reclaimed Doug fir from a yard that specializes in reclaim wood. It's not any cheaper than new wood, but they claimed that these 100-year old wood is more close-grained and stronger than new young wood. This particular pile came from the wine barrels of the Cambridge Winery. Each stake of the barrel was about 12 feet long. They were certainly well-seasoned! Cutting into the wood released a sweet aroma of wine, and people coming into my workshop wonder what's going on in here...

 This picture shows the setup of the frame. The bottom plank is on, and the keelson is also installed. To my amazement, the keelson perfectly mates to the bottom plank!

 

Another view towards the bow. Long strips of Doug fir is used to spile the lapstrakes. The moulds are already shaped with the plank-lands (from the lofting), and the spiling strips are simply placed on the plank-lands, and the shape of the strake held by stapling strips in between. The outer stem, not visible in the picture, has also been mounted. The outer stem is built of white ash, from the ash tree that I cut down in the backyard to make room for a storage shed which was needed to store the contents of my garage.

 

The first strake is done, the second strake getting glued. This picture shows the plywood clamps I built specially for clamping the strakes. My youngest daughter Victoria thinks it's pretty neat.

 

The third strake is done. Each strake is made up of three pieces cut from 8x4 marine ply, scarfed and epoxied together to form a strake of over 20 ft long. For a change of pace, after the third strake I worked on the keelson and this picture shows the keelson covered with three layers of fiber glass. It would then be coated with about 5 coats of thickened epoxy mixed with graphite powder (to reduce water friction) and green pigment. The cost over-run has started...

 

Close-up view of the keelson & bottom. Endless rounds of sanding the keel, epoxying, sounding...has just begun. Visible here also is the plank-lands, filled with loads of epoxy.

 

All the strakes are in, ready for fiber glass. The entire hull was covered with one continuous layer of glass, with a second layer for below the water line. I had one of my daughters, Vanessa, help me with the epoxying as it all had to be done quickly before the epoxy begins to set, in the summer heat.

 

 

Hull is done, waterline struck with a laser surveyor-pointer, now working on the bottom finish with epoxy mixed with graphite and green pigment. As it turned out, the black from the graphite pretty well overrides the green, so the resulting color is very-dark green. It took a few tries before I got the hang of rolling on epoxy with a smooth finish.

 

 

After endless rounds of epoxy and sounding, and filling up any uneven spots, the hull was finally finished. Several coats of special primer were applied first, prior to the hull paint. Here’s what the hull looks like after 5 coats of epoxy, 2 coats of primer, and 2 coats of Interlux paint. I used System Three for epoxy and primer. The primer is wonderful stuff – it hides small imperfections well and wet-sands easily. The sheer strake is left unpainted for now. A strip of 1/4" brass protects the bow, and it extends along the keel bottom. The front and bottom edges of the center board are also protected by a bronze strip. Now she's ready to be turned over...

 

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