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Old 04-10-2012
BryceGTX BryceGTX is offline
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Re: Full or fin keel?

Quote:
Originally Posted by Daily Alice View Post
I am a bit shy to make my first post, though reading this and many other threads for some time, I would like your consideration. Now I am planning a voyage from Hawaii to Japan (my home), and I will purchase a boat in Hon. or NA West Coast, of 34' or under, due to budget.

My question concerns heavy weather. It has been mentioned that fin keels do not heave to. Comments? Also mentioned was that this could be ameliorated with a drogue (like Jordan series)? For the solo or short-handed skipper, in a smaller boat, would the ability of the boat to heave to be a) crucial, b) important, or c) solved by other means?

Of course I would love some recommendations of a used boat suitable to the task for < $25K prior to outfitting. There are not so many choices, right? But would you advise me to ignore any/all fin keels in whatever combination? There is a real appeal in making a speedy passage -- in fact I am wanting to deliver the boat (to myself) in Japan, where it will enjoy its future life, with coastal and offshore work. I am not a circumnavigator, or live-aboard person.

As for sailing experience, offshore experience is limited. I crew on a 37' Jeanneau Sun Odyssey sailing in the Japan Sea, in Southern Kyushu. I do like the idea of weathering battened down in my cabin, reading a book, if it comes to that (or just hanging on).

Last, just to mention, some sort of fin+skeg rudder combination appeals to me (particularly for later coastal use), but I would not want to be foolish. Would you? If you can't heave to with a smaller fin keeled boat, can it be recommended for my (or trans-Pacific offshore) use?
I think in general, the full keel is a much better boat for comfort in rough water. Basically, the more mass righting moment versus hull righting you have the more comfortable the boat. The full keel boat invariably has more keel mass. And has a hull with less hull righting moment. For me, the key number is the ratio of mass righting moment to hull righting moment. For lightweight cruisers and racers, this number is nearly zero. For heavy keel cruisers like the Island Packet, this number is closer to one.

For me, my boat is closer to probably about 0.3 or 0.4. It is a relatively wide beam for speed with a huge keel mass for a significant bit of mass righting moment. It is a trade off. It is not a lightweight cruiser, but it is not a heavy weight like an IP.

It is not so much that you can't take a lightweight crusier in rough water.. because it has been done. However, you need a different strategy in rough water than a full keel boat. Where a full keel boat will be more stable, remain more vertical, the lightweight cruiser will follow the waves on beam. So the way I see it, a better strategy is to keep going or be on a drouge in really rough water.
Bryce

Last edited by BryceGTX; 04-10-2012 at 11:27 PM.
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