Chine and keel questions.

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Cut N Shoot
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Chine and keel questions.

Post by Cut N Shoot »

If a boat has a keel of for lack of knowledge a chine board down the center of the bottom does this make it hard to turn even if you have 1 or 2 inches of rocker? :mrgreen: Sorry for the dumb questions but I have a lot of em. :oops: Waiting on boat plans so I'm makin a huntin bow and it is HOT :evil:
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this side up
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Re: Something I have wondered?

Post by this side up »

The keel strip on a shallow draft boat helps it to track in a straight line.

That helps paddling when making miles but not when going for sharp turns or rapid manuevering.

As to turning a shallow draft or any displacement hull (non-planing), you are having to displace the water so your hull can go where the water was...in essence, you are pushing water....the deeper the hull, the more you displace, the more water you have to push. So shallow is good for easier turns.

Rocker keeps part of your boat out of the water, but that trade off puts more of the middle deeper, but it should result in easier turning...unless the wind is blowing on the increased area that is out of the water.

With a little practice you can learn to do a 180 in about three strokes....but they are mightly strokes and not something you want to do close to any tailiing reds.
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gerald
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Re: Something I have wondered?

Post by gerald »

Anything you put on the hull that's in the water will have an effect upon the handling and performance of the boat. Shape alone should be enough to make a boat go straight and/or capable of turns when you want them. "Keels" were added to many boats because of problems in the design or because of construction constrains--such as you see with an aluminum canoe which has a seam down the middle which is covered with the "keel." I would avoid using a "keel." Sometimes there are trade offs in design--we can accept something that is not so good to accomplish something else--but we need to know that we've made such a trade off.
...and yes...a protruding keel would probably have, at the very least some effect on your turning, and possibly your tracking as well.
Cut N Shoot
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Re: Something I have wondered?

Post by Cut N Shoot »

Gerald thanks for the lesson. I was just wondering since I see a lot of keels and chines sticking out on the boats from the designer I ordered plans from and I'm wondering now if the design is good or if he is like me and well it floats so lets giter dun with a keel to make it float straight till I figure it out why it dont. I may have to get a new mail box key cause I'm wearing mine out lookin in there for plans. :?
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Pogo
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Re: Something I have wondered?

Post by Pogo »

Cut N Shoot, the questions you're asking are on the money, and leading to some very good discussions (good to see you here, this side up); so please remember to put your topic in the header so others can search on your threads later on. :)

I think you hit on very important point in your last reply, and that is to scrutinize whether any plan set you happen to be looking at is the polished result of much blood sweat and tears; a design that has a yard full of prototypes behind it, or is just some CAD wrangler's best shot at what he thinks ought to work best? A good hull design won't need any appendages to help it along. If it's a good design, it can do the job all by its sweet little uncluttered self.
Cut N Shoot
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Re: Something I have wondered?

Post by Cut N Shoot »

Thank for the info and from now on I will post the direct question in the head line. Feel free to adjust any headlines to suit the topic if you can just didn't realize the full extent of what the heading meant to others. :dance:
Cut N Shoot
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Re: Something I have wondered?

Post by Cut N Shoot »

This side up! Captain I posted a reply to your answer but I think it got shafted by other incoming posts. Anyway I thank you for your time and answers. Right on with what the others said.:mrgreen:
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this side up
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Re: Something I have wondered?

Post by this side up »

Pogo, thank you for the welcome.

Actually, I got here by a slight navigational error, but I do tinker a bit with wood so find the discussions interesting. Actually, my background is related but not direct. I have worked in shipyards, and closely with naval architects on ship/load stability moving heavy loads like reactor vessels, offshore platforms, and jackup rigs around the world. So hull stability versus the energy it takes to drive that hull thru the water is always an interesting tradeoff.

And then, I guess the medium for small boats for me is fiberglass....I had a fab shop making petrochem gear and wanted to build/play with building boats..and did. Made huge new boaty mistakes but it was still fun.

I now have two sailboats (FRP), a canoe(Al), three tupperware yaks (they just are so trouble free)..and admire the beauty of the work you guys do on wooden boats, but just don't have the time to devote to making something that is really a functional piece of art.

But don't let me slow you down, let the chips fly.
Cut N Shoot
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Re: Something I have wondered?

Post by Cut N Shoot »

Pogo if I don't get my plans soon I,m going to become a nautical Rookie engineer and design my own. Thanks again for your reply. It sounds like you have been around. Rick
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Pogo
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Re: Something I have wondered?

Post by Pogo »

this side up and all else, nobody requires that you actually build boats to drop in and have fun here. All anyone cares about is that you find it interesting, and maybe even have a little experience to toss in even if only loosely relevant. We never know where the next good idea is coming from.

Cut N Shoot, you bet I've been around . . . certainly long enough to be getting a kick out of your evident excitement in waiting - or NOT waiting :lol: - for those plans to arrive. Not too many people can really understand, but I sure as heck can. 8)
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