If an M-15 weighs 750 pounds then (according to Archimedes) it must displace 750 pounds of water to float. Since a cubic foot of of fresh water weighs 62.42796 pounds, 12 cubic feet of floatation would be needed. Since some of the boat is made from materials that will float when immersed (wood trim, balsa cored deck) then theoretically we could get away with less. BUT, depending upon how your boat is equipped (anchors, chain, outboard etc.) cutting this number down too much is risky. Besides, the deck doesn't float until its in the water. On the other hand, If Jerry says 10 cu ft is enough I'd believe it. Jim On Oct 21, 2009, at 9:45 AM, mrh219@yahoo.com wrote:
While putting my m-15 away for the winter, I finally opened up the bow compartment and found that there was no flotation foam under the cover. I had already noticed that there was no foam at the stern. I am planning to put in two part closed cell foam in the spring, and wonder if anyone has an opinion as to how much foam I will need, or how much weight I need to calculate to determine how much foam. Research seems to show that you don't need pound for pound for fiberglass, but you do for metal such as ballast, motors and spars. So how many cubic feet of foam floats an m-15?
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