San Juan 23 mailing list
|Mobile Geographics||MapTap for PalmOS||CelestNav for PalmOS||IQ Booster for iQue 3600||SJ23||links||tides|
Dan, Mike, et 'al,
We go through a lot of discussions on this board about problems with centerboards, attachment points, cables, fouled centerboard trunks, etc.
Many of us may have formed opinions about the use of centerboards based upon previous experiences--often from experiences with boats featuring keels that served as both keel and centerboard. The SJ23 is obviously different. We never have an option to operate without a keel thanks to the excellent design of our SJ23s. But the centerboard is truly an option to respect and understand.
Our SJ23 centerboard is simply a metal fin, that, while somewhat awkward to handle while repairing the cable and simultaneously standing on your head underwater, is simply a flat fin surface that increases the counterbalance stability under sail --particularly enhancing the boat's reaction to heeling. This fin which extends our draft from 1'-11" (centerboard up) to 4'-9" (centerboard fully down) produces very little drag in straight forward motion, yet increases drag when coming about too quickly, or during tight maneuvering in harborside/marina/docking scenarios. (The weight--approximately 750 lbs. in the fixed portion of the keel-- provides for primary stability.)
Unless you are cornering more than 20-degrees while traveling above 4 knots in the harbor, the centerboard draft is of negligible affect or value. (A more effective technique for creating drag is to "fan" the rudder quickly. Although you'll want to announce your technique to others on board ahead of time.)
Leaving the centerboard down all the time--especially at mooring in saltwater conditions and during high-temp(underwater growth) seasons in freshwater--especially in shallower harbor depths-- invites fouling your centerboard with the same underwater growth that attacks your hull. This also risks fouling the attachment point of your adjustment cable and the clogging of the centerboard trunk on the bottom of the keel. It's the beginning of many more complex problems.
Centerboards are absolutely essential under sail--never risk sailing without one you can control or adjust as desired. Any other time, put 'em back in "the box."
----- Original Message -----