One of the first questions people ask when they discover I mess around with boat designs is: "How do you know it will float?"

Well, making it float is just Archimedes' principle of buoyancy, which we all know about from elementary school: A floating boat displaces water equal to its own weight, and the water pushes upward on the boat with a force equal to its weight. What people usually mean when they ask "How do you know it will float" is really "How do you know it will float upright?"

It's time for another boat parts update! The only way this project is going to make it to completion is if a little bit of work gets done at every possible opportunity. So, slipping in a task or two a day, we are making slow but steady progress on the Starwind 860 trimaran.

The struts that link the 860's crossbeams to her main hull have aluminum end sleeves and a red oak core.

Longer boats are faster. We tend to take that for granted, because it tends to be true. Put two boats of similar type in a race, and the longer one is almost certain to beat the shorter one to the finish line. The difference that length makes is quite remarkable, but we rarely get to look at it on its own- and that is the subject of today's post.