Join Date: Dec 2004
Location: Alameda, San Francisco Bay
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Re: tacking angles
Dixie, you are well on your way… Most sailors don’t really think about tacking angles, VMG and the like. They think that those of us who do are “nuts” to wrangle the last tenth (or is it the last half) knot out of our boats. I just like to sail well…
Standing rigging: What you did using the North guide was to static tune your boat. The next step is dynamic tune. You do this during a sail in your “typical” wind conditions by tightening the shrouds to eliminate the slack on the leeward ones. Then use the Loos to confirm the tension so you can replicate the tension later. Headstay is a little tougher insomuch that you want to reduce (eliminate) the “sag” to leeward (note that this is also adjusted out by using your backstay adjuster). Too much rigging tension will make your boat a pig in light air and too little will make your upper portion of the sail inefficient. Out here in SF, I have a heavy air, “summer”, tension and a lighter tension for the winter. When you are doing your tuning, you want to keep your mast in column and with the proper rake. Too little rake will again, make you boat a pig and not point. Too much and you will have excessive weather helm.
Shroud tension affects VMG. Rake affects tacking angle.
A little war story. Back in ’09 we took the Cal 40 to the Rolex Big Boat Series. We noticed that a Cal, whose owner, with a really big checkbook, had Stan Honey optimize the boat for performance. The thing that struck us was the total lack of lower forward shrouds. The morning of the second day we went aloft and removed ours. Another boat did the same, and another until by the end of the regatta, no Cal 40 had lower forwards. We have been racing that way ever since.
PS. I've been thinking about Gamayun's comments, and you actually might be seeing the effects of leeway in your track. That would show up as an "opening" of the course angle as your boat sags off to leeward. Don't worry, all boats have it.
2000 Catalina 34 MkII