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Re: Chesapeake hull shape
By:Dean Trexel
Date: 10/14/2001, 12:05 am
In Response To: Chesapeake hull shape (Jed)

I haven't done a CLC boat but have done a Pygmy. The hull panels in the middle should only be about 5 degrees or so from horizontal. The flatter the kayak is amidships, the more 'initial stability' the kayak has. There are 2 kinds of stabliltiy, initial and final stability. A kayak with low initial stability would feel 'tippy' or 'squirrly' as you sit upright in it and swivel your hips. It doesn't feel like it takes much of a shift to get the boat to start leaning. If the boat had a deeper V hull, the boat would feel very tippy. Your kayak has a fairly flat bottom to make it less tippy. Final stability, while irrelevant to your question at hand, is represented by the amount the boat can be leaned before it tips over. It's tough to describe without diagrams, so I'd recommend getting Nick Schade's book for reference. But basically, a true V-hull would have low inital stability but high final stability, meaning it would feel tippy at first but you could lean it quite a bit before tipping over, and a true flat-bottomed boat would have high initial stability (like a flat-bottomed fishing boat or Grumman canoe) but couldn't be leaned as far before tipping over. Your kayak was designed as a compromise between the two designs -- sharply Vee'd in the bow and stern for efficiency and almost flat amidships for more stability. You will find that even the most expert-level Greenland-style kayaks have almost flat bottoms -- they're just made much narrower.

Changing a stitch-n-glue design is difficult. The panels will really only go together one way as they are cut, so the only way to modify the design is to make the panels a different shape. Go at your kayak with that Skil-saw at your own risk! :)

Hope that clears things up somewhat...

Dean

: I'm stitching my Ches. 16 hull together and I notice that the bottom is
: virtually flat at the max beam. How much "v" should be there and
: what is the impact of this part of the hull on the yak's performance?
: Should I decrease the beam a bit to get a stronger V shape or just stick
: with the very shallow bottom?

Messages In This Thread

Chesapeake hull shape
Jed -- 10/13/2001, 11:43 pm
Re: Chesapeake hull shape *Pic*
Chip Sandresky -- 10/15/2001, 1:29 pm
Re: Chesapeake hull shape tweaks
Pete Croft -- 10/15/2001, 10:09 pm
Beam reduction???
Randy Knauff -- 10/16/2001, 4:07 pm
Re: Beam reduction???
Pete Croft -- 10/16/2001, 4:56 pm
Re: Chesapeake hull shape tweaks
LeeG -- 10/16/2001, 12:34 am
Re: the ultimate yakin' vehicle *Pic*
Dean Trexel -- 10/16/2001, 1:34 am
Totoro! *Pic*
Ross Leidy -- 10/16/2001, 11:34 am
Re: EEEKK!!
LeeG -- 10/16/2001, 9:36 am
Re: VW gets a nose job
Dean Trexel -- 10/16/2001, 1:06 pm
A woodstrip Westfalia conversion, maybe? *NM*
Shawn Baker -- 10/16/2001, 10:44 am
Re: Chesapeake hull shape
Val Wann -- 10/14/2001, 7:10 pm
Re: Chesapeake hull shape
steve hartmann -- 10/14/2001, 9:48 pm
Re: Chesapeake hull shape
Mike Scarborough -- 10/14/2001, 12:08 pm
Re: Chesapeake hull shape
Dean Trexel -- 10/14/2001, 12:05 am
stability-good designs
Randy Knauff -- 10/14/2001, 12:51 am
Re: flat bottom hull
Bob Marshall -- 10/14/2001, 8:55 am