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posted to rec.boats.cruising,rec.boats.building
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![]() "DSK" wrote in message .. . KLC Lewis wrote: Doug, Essie takes serious exception to the slanderous allegation that she was "poorly built." I told her that you really didn't mean it, but I think it'll be a while before she forgives you. OK, re-phrase that statement so as not to be pejorative. However, there is really no reason for a fiberglass boat to have any measurable flex in it's hull, other than rigidity (and the strength that is a commensurate by-product) not being high on the list of builder's priorities. For example, many years ago a buddy of mine & I went in shares on a fancy racing boat, a 1-Tonner. Several years past it's prime, of course, or we would not have been able to afford it. This boat had been built to be driven *hard* under sail, and stiffness means speed to a racing boat. The tuning guide said that at times, it was possible and desirable to place a tension of 10,000 lbs on the backstay. I spoke to the builder and asked if the boat would really take this, and he laughed and said "Heck yes, when we trialed that boat, we put 20,000 on the backstay and measured a little less than 1/4" deflection along the deck." In years before and since I've worked on and sailed a number of boats, and have found some that flex more, some that flex very little or not at all. Perhaps it's just idle prejudice on my part, but the ones that flex less seem to me to be more desirable. Fresh Breezes- Doug King Well, there's flexing and there's flexing. Essie is built exceptionally stout for a boat of her size, having been built back in '63 before scantlings for fiberglass boats had been developed. In those days they really didn't know how thick things like hulls should be, so they erred on the side of, "I dunno, Frank. Better lay up another quarter inch or so." But a boat on the hard is unlikely to be supported the same way as the water holds her. Essie's cradle supports the keel (full) for a good portion of its length, then there are two supports foreward and two aft (P&S) -- for a total of four. Over the length of a winter, with the hull alternately heating up and cooling off (there are times even in winter when the hull can be hot to the touch during a particularly bright day, only to drop below 20 degrees f at night), this "support" cannot help but put some unusual stresses into the boat. When launched again in the spring, it takes a while for the boat to relax into the water. Again, with Essie we're talking fractions of fractions, but it's still noticable. And she is WAY stronger-built than she needs to be. The flexing we are talking about isn't "oilcanning" from scantlings that push the lower limit. |