The daggerboard case



Today I sorted out the daggerboard case.  It is the focus of quite a lot of stress during sailing, not a component to be underbuilt.  It wasn't clear to me how best to integrate it with the midships thwart and the floors at stations 2 and 3.  My MO is to work through it a a component at a time, and see if they all work together.  I just don't have the experience to lay it all out on paper and do it.

At a late moment, I decided to make the dagger board only 9 inches fore-and-aft (the plans specify 12), and the slot in the bottom is 12 1/4 inches long.  My reasoning was that I've seen lots of daggerboards for small boats closer to 9 than 12, and on Ripple, storage is an issue, and a 9 inch board would be easier to stow.  Oh, and I had a suitable piece of sitka spruce 9 inches by 4 quarters.  And straight and true.

This meant re-engineering the case verticals to fill in the 3+ extra inches.  Doing so has the additional benefit of strengthening the whole assemblage, both by increasing the gluing area of the case verticals and the case cheeks, and by extending these verticals down into the 12 inch slot to the bottom of the keel.  The first image shows these verticals.  Note that they are notched to bear on the floors at stations 2 and 3.

From that point, it was a matter of working out the dimensions of the case logs (the pieces that meet the keelson and the cheeks), the forward end cap, the upper rails (that also help support the thwart), and the top cap.  It all fell into place, though it is not entirely clear to me at this time what the sequence of assembly should be.  

I am very pleased that the case and the floors and thwart will all be integrated both structurally and visually.  I think it should work well and long.


Below is a picture of my benchtop at the end of 5 satisfying hours of work on these components.  Uncharacteristically, I cleaned it up before I left for the day.


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