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Old 03-02-2013
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Re: Full or fin keel?

Quote:
Originally Posted by outbound View Post
Believe the properly designed centerboarder is a joy. Another way to adjust point of lateral resistance and of reducng draft at will are blessings. Still even with well executed designs have had some bad experiences. Irregular noise as the boat rolls in quartering seas on a trip back from Bermuda kept the crew from sleeping soundly ( Boat was a Hinckley). Jammed from gravel some how while crossing from Southwest Harbor to P town (boat was a Seguin if I remember - still don't understand how that happened - boat was nowheres near shoal water at anytime-was told needed a haul to clear). Regardless of how well done it's difficult to get a elliptical keel to have as effective hydrodynamics as a dedicated fin ( chord will vary as deployed and usually low aspect) and of course a bulb is a more effective lever arm than even a weighted board and internal ballast. Paulo mentions the Boreal and course there are the Southerlies and Ovnis making good use of this technique at present. Never had the pleasure of owning one but sure have had frustating days helping friends maintain them and their trunk/pendant and pin.Wish you joy of her Faster. Agree your decision is a excellent one on the east coast but looking at noon to noons thought to go a different way.
Several comments:

1. The Sequin 40 (if that's what is was) was designed by Craig Walters and looks like a bigger version of my Clearwater 35, also a Walters design. The Clearwater 35 has 2500# of lead ballast inside the leading edge of the NACA shaped keel, according to Barrett Holby, the builder. (An additional 2500# of lead is glassed into the rather slack bilge.) i would estimate that my swing keel is pushing 3000#. It's hard to imagine jamming the keel in its trunk due to gravel or mud, as can be the case with a conventional centerboard. I am assuming the Sequin 40 has a larger version of my ballasted keel, so its hard to imagine jamming it.

2. The Sequin 40 and Clearwater 35 are not true centerboarders. the bottom is whaleback-shaped and there is no stub keel , which allows them to be beached like a Southerly. The lack of a keel means my draft is 1' 10" with everything up (including the rudder). You could sail my boat like a centerboarder by varying the amount of keel down, but that leaves the trunk slot open and would produce turbulent flow. When the keel is all the way down, the trunk slot is closed. If I am in deep enough water, and can live with a 5' 11" draft, I leave the keel all the way down. BTW, the PHRF rater had my displacement at 12,500#, despite what the spec sheet below says.



3. The elliptical keel is a compromise. Aside from the difference in waterline length, some folks compared the Clearwater 35 (on paper) to the J-35, which has a more hydrodynamically-efficient fin keel. When the PHRF folks got through and there was an opportunity to compare them on the water, it was quite clear that the fin keel made for a faster boat--that and a ton less weight, longer LWL, and 20% more sail area for the J-35.

4. My offshore experience is limited, but we made the 600 mi. from Ft. Pierce, FL, to Beaufort, NC, in 72 hours, sailing all the way until within sight of Emerald Isle, when the wind died down. We went offshore to get the Gulf Stream boost, but that's still good time, and the boat motion was easy. So, I don't think our speed compared to LWL needs any excuses. Also, we won our very first race (cruising category) in a field of 13 or so other boats, including a Cardinal 46 that has participated in the Newport Bermuda race. We won it in actual as well as corrected time, perhaps because we outpointed every boat in the fleet when it mattered. Unfortunately our racing career went downhill after that!

5. Our maintenance issues with the swing keel have been minimal. We replaced the 1.5" dia, pin after noticing pitting corrosion at the seals. The original appeared to be 304 SS, whereas the replacement is 316 SS and is going on 13 years with no problems. I've replaced the nylon pennant once, on a precautionary basis. The retractable rudder was more troublesome until we replaced the original aluminum rudder trunk with a composite structure to eliminate binding. Overall, maintaining this retractable system has not been much of a problem once we fixed the items mentioned.

One last comment, another keel type to consider is the retractable, weighted daggerboard that is used in the Hake designs. You've got an efficient foil shape, ballast bulb to keep the CG low, and you also have shallow draft when you need it.
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