Keel Construction

The keel is the next component to be made for the dinghy. Its final length is planned to be 6 feet long, so I am making an 8 foot long timber out of douglas fir which will let me cut it down to the needed dimensions.

Just like the stem, I am fabricating this timber out of two planks of quarter sawn lumber. Just like the stem, the keel is cut out of a flat sawn board that was next to the heart. When I ripped the board down the middle, the two remaining pieces are quarter sawn and will be much more dimensionally stable. Book matching the boards will also increase the dimensional stability of the keel as the grains will oppose each other and prevent any warpage from taking place.

To ensure that the boards will match up perfectly, I need a very tight joint. Running the boards on the jointer provided me with a smooth face that will provide the best gluing surface. The problem is my jointer is rather small and the keel timbers are very large, making this a difficult task. 

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After the faces were smoothed, I still had this one bump. I decided to plane this down by hand instead of taking off an entire layer of wood again.

Reducing the high spot, the two faces were able to meet much closer. This makes for a tighter joint which will result in a stronger bond. Ideally, the two boards would be perfectly perfect, but the truth is, this is on an end with knots, so it will end up being cut off during later construction of the dinghy.

After planing the bump in the board, the two faces meet much more evenly. The little gap will be removed when the two boards are clamped together.

The excess glue that squeezed out doesn't need to be cleaned since the entire face will be cut off when the keel is shaped. The squeeze out is actually wanted, as it lets you know that the entire face is covered with glue. If you glue the two boards and no glue squeezes out, you can assume that either you had the perfect amount of glue or not enough glue. More likely than not, there was not enough glue and the resulting dry spots will not be glued together, creating a weak bond and a location for moisture to collect. The moisture that will collect between the faces will cause the boards to rot from the inside out. 

An important note with clamps is to alternate the sides the clamps are on. If you put all the clamps on the same side, the combined pressures will induce a twist into the boards. This can cause distortion in the glue up, producing a bowed product. By alternating the direction the clamps are placed will help cancel out this tendency and produce a straight glue up.

Now the assembly can sit and cure for the next day or two before I take it out of the clamps and clean up the sides on the band saw, just like I did for the stem.

With the stem and keel glued up, I can begin positioning them to create the gripe that will hold these two pieces together. While construction will seem slow in these stages, once the backbone is completed, the dinghy will appear rather quickly from the pile of lumber.

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