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Re: SO kayak dream
By:Paul G. Jacobson
Date: 3/8/2000, 10:59 pm
In Response To: Re: SO kayak dream (Hans Friedel)


> . . . But a long hull also has more wetted surface.

That is not necessarily the case. It depends on where that length in added. If you make the hull 6 inches longer (about 15 cm) by stretching the area in the center of the boat, then (assuming the boat is 24 inches or 60 cm at the waterline) you will add about 6x24 square inches to the wetted area or about 15x60. sq cm. that would be 144 square inches or 900 sq cm. however, if you make the boat 1 inch ( 2.5 cm) narrower, and that inch reduction is carried over the 17 foot length (roughly 2.6 m) then you will have a reduction of 17 x12x1 inches or 204 sq inches, so you end up with 60 square inches LESS wetted area on the longer and narrower boat. In practice you probably can not take an even inch off of the width along the entire length onf the boat. you would take off more in the middle of the boat, and taper your reduction as you came to the ends. Even so, if you could reduce just 12 feet of the middle of the boat by that inch, your longer boat should have the same or slightly less wetted area than the shorter, wider boat. The length and width I used above were taken to make the math a bit simpler, and not to be representative of any particular kayak model. The principle should work, though. I think it is just a matter of finding the proper numbers. It might be that you could get by with narrowing the hull only 1/2 inch, or mayber you would need to narrow it by 2 inches. I suppose it depends on the original design and where you are adding the inches to the length. If anyone can plot this out on a computer I'd be interested in seeing the results.

Just a few rambling thoughts

Paul G. Jacobson

> My newest project is a
> 15'8" kayak and this kayak is more easily driven at speeds from 0-5
> knots than my race kayaks. Due to less wetted surface. So for a light
> paddler 50-70kg+ stuff I think a 16' kayak will do fine

> But of course there is always the " Hey Dude thats a migthy long boat
> must a god one?? huh"

> Hans

Messages In This Thread

SO kayak dream
pete czerpak -- 3/7/2000, 7:42 am
Re: SO kayak dream
Todd -- 3/8/2000, 1:09 pm
Re: SO kayak dream
Paul G. Jacobson -- 3/7/2000, 11:17 pm
Re: SO kayak dream
pete czerpak -- 3/8/2000, 8:55 am
Re: SO kayak dream
Hans Friedel -- 3/8/2000, 6:20 am
Re: SO kayak dream
Paul G. Jacobson -- 3/8/2000, 10:59 pm
Re: SO kayak dream
Hans Friedel -- 3/9/2000, 12:38 am
Re: SO kayak dream
Robert Woodard -- 3/7/2000, 5:07 pm
SO many acronyms...
Marcelo 9 7/8 -- 3/7/2000, 1:11 pm
Re: SO many acronyms...
Paul C. -- 3/8/2000, 12:19 pm
Re: SO many acronyms...
Dale Frolander -- 3/8/2000, 12:46 pm
More acronyms...
Shawn Baker -- 3/7/2000, 5:43 pm
Re: What about DAM?
Spidey -- 3/7/2000, 5:31 pm
Re: And BIDS
Don B -- 3/8/2000, 12:07 am
Re: SO many acronyms...
Mike Hanks -- 3/7/2000, 1:21 pm
Re: SO many acronyms...
Mark B -- 3/7/2000, 1:19 pm
Re: Kayak Building and Couples Time
Tim Stough -- 3/7/2000, 12:35 pm
Re: Kayak Building and Couples Time
Mike Hanks -- 3/7/2000, 12:53 pm
Re: Lucky!
Don Beale -- 3/7/2000, 3:01 pm
Re: SO kayak dream
Shawn Baker -- 3/7/2000, 10:18 am
Re: SO kayak dream
Ken Finger -- 3/7/2000, 9:39 am
Re: SO kayak dream
pete czerpak -- 3/7/2000, 7:44 am
Re: SO kayak dream
Ross Leidy -- 3/7/2000, 8:41 am
Re: SO kayak dream
Chris Bush -- 3/8/2000, 9:28 am
Re: SO kayak dream
Larry Thompson -- 3/8/2000, 7:02 pm