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Old 14-05-2008, 03:23   #1
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Wink Daggerboards ??

Hi all, just got back from a sea trial on a Catana 411 . Great boat, great design. Question for you all.
In cruising terms what would you consider an advantage a dagger board for closer to wind performance, or normal cat keels, without a dagger board. Sailing med first then across the pond.
The system on the Catana was very easy to use.
PS. We are still looking for an ideal cat. The Catana 411 certainly comes close.
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Old 14-05-2008, 06:00   #2
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There are plusses and minuses. I think they give you the ultimate performance, but you need to tend to them.
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Old 14-05-2008, 07:56   #3
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Hi redbreast - the 411's are very well regarded boats. I suggest you post questions about that specific model on the Catana Owners Forum > CatanaCats : Catana Catamaran Owners & wanta be's

As for boards, windward performance is significantly enhanced and having the ability to raise the boards when you want leewway, as when broadside to breaking waves, is a safety feature. The downsides are higher cost, more complexity, no "guardian" for the shaft/drives, props, and rudders, and less flexibility for beaching. Pick yer poison.

Because I'd rather sail a boat than merely steer one one, I was partial to boards.

Dave
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Old 14-05-2008, 13:28   #4
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Leeway and safety

"having the ability to raise the boards when you want leewway, as when broadside to breaking waves, is a safety feature." Says Shuttleworth. Kelsall says "No way, You'd have to accelerate to 20 knots in a second for that to work." You pays your money and takes your choice-
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Old 14-05-2008, 13:36   #5
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Kelsall says "No way, You'd have to accelerate to 20 knots in a second for that to work." You pays your money and takes your choice-
Intuitively, and as shown underway, boards up vs fixed keels will permit some amount of leeway, sometimes a lot.

Want to refute that?

No one can predict how much leeway will be needed for future events.

Some leeway is better than none, and may be enough. Thus, safety is improved. No guarantees, just improved.

Dave
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Old 14-05-2008, 13:48   #6
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2Hulls, the debate is about going sideways in breaking waves, not about leeway. Leeway is caused by wind. Naturally you'll make leeway if you have dagger boards down and pull them up. And it's not me you are arguing with, but Derek Kelsall. I don't have a position on the subject, though it looks like you do. I don't find your remarks to be a convincing argument for Shuttleworth's position, however.
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Old 14-05-2008, 14:00   #7
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2Hulls, the debate is about going sideways in breaking waves, not about leeway. Leeway is caused by wind. Naturally you'll make leeway if you have dagger boards down and pull them up. And it's not me you are arguing with, but Derek Kelsall. I don't have a position on the subject, though it looks like you do. I don't find your remarks to be a convincing argument for Shuttleworth's position, however.
Of course I have a position on the subject - and it's intuitively obvious that no boards will permit more leeway, sideslip - whatever you want to call it - than fixed keels. Only a fool would disagree with that. Whether enough leeway is permitted for a given situation is an entirely different matter. No one can predict that, not even Mr. Kelsall nor Mr. Shuttleworth - or even you.

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Old 14-05-2008, 14:06   #8
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So, Dave, you are willing to call Derek Kelsall a fool? Do you know his background and history? Do you really know so much more about multihull design and sailing than Derek Kelsall does?
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Old 14-05-2008, 14:34   #9
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So, Dave, you are willing to call Derek Kelsall a fool? Do you know his background and history? Do you really know so much more about multihull design and sailing than Derek Kelsall does?
BC - you're either missing the point or misread what I wrote.

If Derek disagreed that no boards will permit more leeway, sideslip - whatever you want to call it - than fixed keels, yes, I'd call him a fool. But he wouldn't disagree with that. Who would?

My point - that you apparently are missing - is that no one can predict how much leeway/sideslip would save a cat from tripping over it's hulls from breaking waves. And that more leeway/sideslip is intuitively better than less leeway/sideslip in those situations. With all due respect to Derek - he cannot predict in advance, and no one else can - how much leeway would be needed for a given situation and intuitively, a little more - the amount permitted by raising boards - may save the day, and hence is safer. Do you not understand this simple point?

Dave
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Old 14-05-2008, 16:17   #10
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To get back to the original question. Daggerboards make a better sailing boat. No question about it. Unfortunately those turtles cats we see posted on the net are usually these boats with the boards down when they shouldn't have been down. The last one I can remember happened during a race in the Great Lakes. It was night and the watch changed, the boards were down and a blow occurred and they couldn't get the boards up fast enough. The boat overturned.

As stated earlier, boards are good but have to be tended to 24/7. Sh%&t happens when you least expect it.
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Old 14-05-2008, 16:25   #11
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Originally Posted by 2Hulls View Post
Hi redbreast - the 411's are very well regarded boats. I suggest you post questions about that specific model on the Catana Owners Forum > CatanaCats : Catana Catamaran Owners & wanta be's

As for boards, windward performance is significantly enhanced and having the ability to raise the boards when you want leewway, as when broadside to breaking waves, is a safety feature. The downsides are higher cost, more complexity, no "guardian" for the shaft/drives, props, and rudders, and less flexibility for beaching. Pick yer poison.

Because I'd rather sail a boat than merely steer one one, I was partial to boards.

Dave
Why couldn't dagger boards partially down protect the drives and rudders just like a keel does?
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Old 14-05-2008, 16:51   #12
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Why couldn't dagger boards partially down protect the drives and rudders just like a keel does?
That's a good point, David M, and I do that myself sometimes. I have my boards marked at the depth that equates to the depth of the rudders (the sail drives are shallower) and they work very well as analog depth sounders. It makes sense on a passage at night to similarly lower the boards in case that barely floating container is encountered.

Dave
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Old 15-05-2008, 23:30   #13
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Smart idea Dave!
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Old 16-05-2008, 12:26   #14
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There's something that has always bothered me abut the notion that fixed keels or a partially lowered daggerboard will protect the props and rudder. It makes sense but the thing that bothers me is that a floating object is, by definition, floating. Once the keel/daggerboard has struck the object the boat (hopefully) will ride up over it but then, since it is still floating, the object is theoreticly free to bump the rest of the appendages.
I have a nice, deep keel on my Catalina but whenever I do a channel crossing I find kelp wrapped around the base of the rudder which may indicate that while the keel pushes it down, it pops right back up again. Most of the floating debris I have hit over the years such as logs are pushed to the side by the hull, not deflected by the keel. I just wonder if we are giving fixed keels on multi's more credit than they are due.

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Old 16-05-2008, 13:25   #15
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Here's what happened on my monohull with a full keel and attached rudder when I would hit a telephone sized log-there are lots of these around here, due to logging-It would disappear, and then float to the surface about 150 feet aft of the boat. These logs lie at right angles to the boat's course, because the wind blows down the channels, (see a map of the Pacific NW of the US and the adjacent portion of Canada,) and the logs lay parallel with the waves. My best guess is that I rode right over the logs. My conclusion is that if you are concerned about debris, you'd better give your rudders a full, beefy skeg, connected to the rudder, with the props in between. Your boat may not sail quite as fast, but you will keep your rudders and props despite debris and groundings. If you look on my website you will see that I practice what I preach-
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