by FastCrab » Fri Oct 22, 2010 7:40 am
OK- I performed my test using a boathook pointer as a measurement of flexibility yesterday.
The goal: To see if this flex is a big worry, or if the keel will be OK to sail till I haul the boat for the season. A quick calculation indicated the pointer should move about 1.047"for each degree of flex laterally, giving me a quantifiable value.
Method: I cut 2 wedges of wood, and used them to wedge said boathook in the bottom of the keel sump, aft of the last floor beam where I could get to it. It needed to not touch anything else, so was extending at an angle sufficient to clear the shaft and the plywood. The boathook was now a valid pointer which should indicate lateral angular movement of the bottom portion of the keel sump with respect to the rest of the hull. The pole was then extended to within 1/2" of the cabin top inside. I put up a #3 and the main and sailed with only 2 crew in about 12-15 Knot slightly gusty NW winds in the Potomac, between Tall Timbers and Ragged Point. The NW wind created a fetch coming down the Potomac, so we had 1.5-2.5 ft waves with the occasional larger (3ft or more) rogue. We sailed an easy close reach up wind and then beat for a time, then reached down, still with the #3. Even in this setup and no rail meat to speak of, the Evelyn achieved a maximum speed of about 7.7 Knots...
Results: the pointer moved 3/16 of an inch, and then only coming back in off a wave, with some extra movement from the boathook's own flexibility. There were some pretty airborne re-entries. We also did some quick maneuvers under power inside the protection of Herring Creek.
Conclusions: It appeared plenty stiff. I am not the least bit afraid to sail this boat until haul-out this year, other than the risk of more delam if there is some. My biggest mistake in this experiment was I had the guy who had just test sailed 'Blown Away', the Maxi 87 boat I am selling, on board- he now realizes he may want a faster boat...!