Builders' Forum Archives
Re: How to change the NB
Posted by LeeG on Mar 28, 2008
simple, I'd build a Guillemot Night Heron if I wanted a fast maneuverable kayak or a Merganser 18 if I wanted a stiffer tracking fast kayak or an Arctic Hawk for something inbetween.
"Add some rocker More bow volume (or perhaps less stern volume?) Change the flare of the sides??? Skeg if changes don't fix weathercocking "
That's essentially what I did, then you build another and another until it's just right if you discovered something didn't turn out right the first time around.
You're kind of hamstringing the effort to change the hull shape in the ends of a very skinny kayak if you retain the pre-glued sheer clamp construction technique as some bends cannot be done in 4mm with a 3/4" sheer clamp glued on.
Try it,,get a 24"x6" length of 4mm ply and bend it. Then get a 3/4"x1"x18" cypress sheerclamp then bend it. It doesn't bend as much. Now glue the cypress on the 4mm,,it will bend even less. The amount of volume you can develop above the waterline in the bow is somewhat connected to the curve you can develop and not just by the height of the bow.
It's not noticable in a 28" wide kayak, it starts to become noticable as the kayak gets narrower and become critical as the kayak gets down to a 20" Northbay. Developing a lower volume sharp v stern is a reasonable attribute, it's a good place to put a skeg or a rudder. But it's not that great in the bow. I noticed this making my version of the Northbay, after I stitched it up I had beam dimensions the plywood was supposed to take in the ends and it was not possible. If I tried to force the side panels apart to the drawn dimensions and bend the sheerclamps it would have ripped the plywood apart. So I set it as far as it would go and noticed the profile at the bow and stern resulted in a flattened rocker with the ends being sharper than intended. It can be tolerated in the stern more than the bow. But if you want to really change the bow for an improved NB,,eliminate the sheer clamps.
In Response to: How to change the NB by Frankp on Mar 28, 2008