Building the Backbone: Test Fitting

When I built Tooth, I never actually measured the space on the deck. I loaded Tooth onto the deck and realized that it didn't actually fit between the mast and dodger. I felt like a fool for not actually measuring the space available before building the dinghy. To avoid repeating that mistake, I am test fitting the backbone on the deck before further construction.

The dinghy needs to serve as our dinghy, but it also needs to cover the salon hatch (which leaks) and not cover the chimney. Since fitment is not a simple length requirement, I wanted to see it on the deck and make sure everything had plenty of space.

I tried positioning the backbone in various positions, measuring to see which position would give me the most displacement capacity. My requirements are it must cover the hatch and not cover the chimney. To avoid covering the chimney, the dinghy will be mounted backwards on the deck, stern facing forward and bow facing aft. 

Two positions shined as the most feasible, straight, with a carrying capacity of 897 pounds, and angled with a carrying capacity of 1091 pounds. The angled position would allow the bow to be bulkier, which is where the difference in displacement is made, but the stern needed to be a bit narrower. The bulkier bow would not be big enough for cargo but would offer more resistance when working into waves. The straight position offered a more slender bow with a narrow angle of entry, allowing the bow to cut through waves more easily and a wider transom which will offer more cargo space in the stern.

The final decision was actually based off of aesthetics, and not function. If the dinghy were set at an angle, it would look odd. Because of this, we decided to build the dinghy based on the straight orientation.

The keel was separated into 1 foot sections and the maximum distances for beam were measured. These distances would not produce a fair hull, but they are the maximum size that would fit.

Now that I know that the backbone fits on the deck and I can finalize the design and finish building the rest of the dinghy!

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