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Re: kayak shape/design?
By:Paul G. Jacobson
Date: 6/8/2001, 4:50 am
In Response To: kayak shape/design? (Mark)

: Also, I would like to know what a 'fish-form' is.
: What distinguishes it and what is it good for?

There are three basic forms to kayaks and canoes:

1) symmetrical. The widest spot is in the cneter of the boat -- equidistant from either end. This is the basic shape for all those old Grumman aluminum canoes. The left side of the boat was stamped on the same die as the right side, and both symmetrical pieces were riveted together.

20 Fish form. In this type of boat the widest spot is closer to the bow. In an extreme case the widest spot on a 16 foot long boat might be 4 feet from the bow, with the remaining 12 feet slowly tapering back to the bow. If you look at the shape of a large fish from above you get the idea: Big around the gills, then it tapers along the length of the fish to a very thin tail. Because of the dragging tail end on such a boat there is some believe that it might track better with a solo paddler, however by putting the widest part of the boat so far forward the entry angle is rather steep, which might slow down the boat a bit.

3) Swede form. This is the fish form reversed. The widest part of the boat is behind the center. With a long,sharp taper leading up to that bulge, these boats have narrow entry angles, which should (in theory) contribute to slightly higher speed. Boats of this style have been rather popular with some racers. You'll see this style more in singles than in doubles, as the person in the bow is going to feel rather cramped unless they are a lot skinnier than the stern person.

Most current sea kayak designs seem to be slightly Swede form, with long tapering bows leading to the cockpit, which is wide enough for the paddler, and not much more. The wider stern, helps provides the bouyancy close to the center of gravity, or balancing point, or center of flotation, which is usually right in front of the paddler's torso.

hope this helps.


Messages In This Thread

kayak shape/design?
Mark -- 6/8/2001, 4:15 am
Re: kayak shape/design?
Mike Hanks -- 6/8/2001, 9:44 pm
Re: kayak shape/design?
Shawn Baker -- 6/9/2001, 12:51 pm
Re: kayak trip OT
Ted -- 6/11/2001, 12:47 pm
Re: kayak shape/design?
Jim -- 6/8/2001, 1:49 pm
Re: kayak shape/design?
Paul G. Jacobson -- 6/8/2001, 4:50 am