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Re: Strip: Center of Buoyancy calculation
By:Bill Hamm
Date: 8/30/2012, 2:37 am
In Response To: Re: Strip: Center of Buoyancy calculation (PatrickC)

: since you changed the design...you put yourself in the realm of not
: knowing if you got it right for sure
: or not.

: I designed my own, and based my cockpit location by about what a
: similar kayak would have, by eye.

: Rather than risking having to re do the coaming etc..i taped the
: deck on without a coaming...
: just the strips glassed with the approximate key hole shape cut.
: then sat in the boat on a rolled towel to see the
: balance....also i put it in the pool...then i had my kid sit in
: it and took a couple pictures from the side...and saw that the
: stern looked a little higher out of the water than it should be
: even though the towel test and my own sit in seemed ok.

: I ended up lengthening the cockpit aft 6". So by eye I was
: pretty far off, but no biggee since i did'nt have the coaming
: done yet.

: End result is I got it right by trying different things.. I would
: think if you do a rolled towel balance test it will be in the
: ballpark...and then add a couple inches aft with your coaming
: like i did so you can adjust your seat position a bit more to
: compensate for error.

: http://www.youtube.com/watch?v=2tvNsksPqD4&feature=plcp
: https://vimeo.com/19844829

The towel method would be good for finding the center of weight, not necessarily the same as the center of bouyancy though. You're looking for the volume rather than the weight, can be considerably different, specially depending on deck shape which doesn't count.

Bill H.

Messages In This Thread

Strip: Center of Buoyancy calculation
Gordon -- 8/28/2012, 9:48 pm
Re: Strip: Center of Buoyancy calculation
Eric Compas -- 8/28/2012, 10:36 pm
Re: Strip: Center of Buoyancy calculation
Bill Hamm -- 8/29/2012, 2:59 am
Re: Strip: Center of Buoyancy calculation
JohnK -- 8/29/2012, 3:04 am
Re: Strip: Center of Buoyancy calculation
Allan -- 8/29/2012, 4:01 am
Re: Strip: Center of Buoyancy calculation
Gordon -- 8/29/2012, 7:47 am
Re: Strip: Center of Buoyancy calculation
PatrickC -- 8/29/2012, 1:42 pm
Re: Strip: Center of Buoyancy calculation
Gordon -- 8/29/2012, 3:38 pm
Re: Strip: Center of Buoyancy calculation
PatrickC -- 8/29/2012, 5:31 pm
Re: Strip: Center of Buoyancy calculation
Gordon -- 8/29/2012, 6:17 pm
Re: Strip: Center of Buoyancy calculation
Bill Hamm -- 8/30/2012, 2:37 am
Re: Strip: Center of Buoyancy calculation
Joy -- 8/29/2012, 3:12 pm
Re: Strip: Center of Buoyancy calculation *PIC*
Etienne Muller -- 8/29/2012, 4:48 pm
Re: Strip: Center of Buoyancy calculation
Stephen Troy -- 8/29/2012, 5:05 pm
Re: Strip: Center of Buoyancy calculation
Etienne Muller -- 8/29/2012, 6:05 pm
Test Paddle to Eliminate Weathercocking
Dave Houser -- 8/29/2012, 6:57 pm
Re: Test Paddle to Eliminate Weathercocking
PatrickC -- 8/30/2012, 1:58 am
Re: Strip: Center of Buoyancy calculation
Marc Upchurch -- 8/29/2012, 7:17 pm
Re: Strip: Center of Buoyancy calculation *PIC*
Etienne Muller -- 8/30/2012, 6:56 am
Re: Strip: Center of Buoyancy calculation
Allan -- 8/30/2012, 2:00 am
Re: Strip: Center of Buoyancy calculation
Paul Sylvester -- 8/31/2012, 9:41 pm