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Re: Other: advice on tandem sea kayak designs
By:Allan
Date: 12/5/2013, 5:25 am
In Response To: Re: Other: advice on tandem sea kayak designs (Bill Hamm)

Beam works on length, two boats with the same hull section shape one being much longer but with the same beam as the other will be much more stable.

Said another way, for your example, a very short 24" wide boat will be considerably tippier than a a boat with the same section shape and beam that's say 16' long. The overall beam on the short boat is only for a very short distance before it tapers back to the pointed ends, it's a much more full shape on a longer hull where the maximum beam carries for more distance.

Bill H.

That is true, but it is slightly more complicated than that. As you explain, you need to consider how much of the length of the kayak is at or close to the maximum width.

In theory it is possible to have a fixed width and to create a longer kayak that has less stability. It is possible for a shortish kayak with very full ends to have more stability than a longer kayak that has very fine ends and only a very short section in the middle that is wide.

On another forum, I provided an illustration of how two kayaks with the same width could have very different levels of stability. In fact one could have four times the righting moment without changing the width.

http://www.blueheronkayaks.com/phpBB2/viewtopic.php?f=2&t=1825&p=17978&hilit=width+and+stability#p17806

Of course some of the time when we mentioned width, we meant waterline width.

There are quite a few factors that affect stability. As you explain, width is just one of them.

Messages In This Thread

Other: advice on tandem sea kayak designs
mike_c -- 11/30/2013, 9:18 pm
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 11/30/2013, 10:47 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/1/2013, 12:20 am
Re: Other: advice on tandem sea kayak designs
scottbaxter -- 12/1/2013, 1:24 am
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/6/2013, 10:49 am
Re: Other: advice on tandem sea kayak designs
Marc Upchurch -- 12/6/2013, 12:39 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/7/2013, 11:45 am
Re: Other: advice on tandem sea kayak designs
Marc Upchurch -- 12/7/2013, 12:12 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/8/2013, 12:13 am
Re: Other: advice on tandem sea kayak designs *PIC*
Rob Macks/Laughing Loon CC&K -- 12/1/2013, 11:55 am
Re: Other: advice on tandem sea kayak designs
Ric Moodie -- 12/1/2013, 11:57 am
Re: Other: advice on tandem sea kayak designs
aedie -- 12/1/2013, 2:30 pm
Re: Other: advice on tandem sea kayak designs *PIC*
Etienne Muller -- 12/1/2013, 2:43 pm
Re: Other: advice on tandem sea kayak designs
JohnAbercrombie -- 12/1/2013, 3:23 pm
Re: Other: advice on tandem sea kayak designs
Nick Riccardi -- 12/1/2013, 3:54 pm
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/1/2013, 6:43 pm
Re: Other: advice on tandem sea kayak designs
Nick Riccardi -- 12/2/2013, 10:56 am
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/3/2013, 12:20 am
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/3/2013, 12:29 am
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/4/2013, 12:24 am
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/4/2013, 10:11 am
Re: Other: advice on tandem sea kayak designs *PIC*
Rob Macks/Laughing Loon CC&K -- 12/4/2013, 11:13 am
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/4/2013, 1:23 pm
Re: Other: advice on tandem sea kayak designs
Marc Upchurch -- 12/4/2013, 1:32 pm
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/4/2013, 1:49 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/5/2013, 2:21 am
Re: Other: advice on tandem sea kayak designs
Paul Davies -- 12/4/2013, 3:33 pm
Re: Other: advice on tandem sea kayak designs
Etienne Muller -- 12/4/2013, 3:48 pm
Re: Other: advice on tandem sea kayak designs
Paul Davies -- 12/4/2013, 4:32 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/5/2013, 2:33 am
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/4/2013, 6:57 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/5/2013, 2:14 am
Re: Other: advice on tandem sea kayak designs
Allan -- 12/5/2013, 5:25 am
Re: Other: advice on tandem sea kayak designs
Etienne Muller -- 12/5/2013, 1:52 pm
Re: Other: advice on tandem sea kayak designs
Nick Schade - Guillemot Kayaks -- 12/5/2013, 4:50 pm
Re: Other: advice on tandem sea kayak designs
ancient kayaker -- 12/5/2013, 6:24 pm
thanks for the advice so far!
mike_c -- 12/1/2013, 5:00 pm
Re: thanks for the advice so far! *PIC*
Paul Davies -- 12/1/2013, 7:44 pm
Re: thanks for the advice so far!
Rob Macks/Laughing Loon CC&K -- 12/2/2013, 5:33 pm
Re: thanks for the advice so far!
Paul Davies -- 12/2/2013, 8:28 pm
Re: thanks for the advice so far!
Nick Riccardi -- 12/4/2013, 6:19 pm
Re: thanks for the advice so far! *PIC*
Kyle T -- 12/2/2013, 9:09 am
Re: thanks for the advice so far! *PIC*
Sean Dawe -- 12/2/2013, 12:45 pm
Re: thanks for the advice so far!
Dan Caouette (CSCWC) -- 12/2/2013, 1:16 pm
Re: thanks for the advice so far!
ancient kayaker -- 12/2/2013, 5:08 pm
Re: thanks for the advice so far!
Bill Hamm -- 12/3/2013, 12:35 am
Re: Other: advice on tandem sea kayak designs *PIC*
Sean Dawe -- 12/3/2013, 9:29 am
Re: Other: advice on tandem sea kayak designs
JohnAbercrombie -- 12/3/2013, 2:42 pm