: Hi guys,

: I'm planning to build an SoF soon. For the particular application I want it
: to be relatively short (13-14') and stable - I'm thinking say 24"
: wide. (Paddler weight c. 170lbs.) I'd like to do it as a simple single
: chine design, but that got me thinking - how wide is too wide for a single
: chine SoF? There must come a point where the unsupported skin on the
: bottom is too wide and starts behaving "badly" - although I'm
: not sure what the first symptoms would be.

: Anyone with views / experience?

: Any recommendations on what fabric / coating to use to be stable on wider
: kayaks?

: thanks,

: Dave.

Hi Dave,
The maximum space between skin support will vary with the weight of the cloth, the heavier cloth will stiffer but takes more coating. This makes it even stiffer but heavier again.
How straight the ribs are between chines plays a factor as well. Ply frames can be shaped to give maximum space by hollowing out the ply between the ribs. Steam-bent would need very tight bends at the chines to keep the remainder areas as straight as possible.

For some specifics, my kaykas are canvas skinned and the biggest spacing is about 6" on my greenlander. My playboat has a similar chine width but I had to put an 'extra chine' between the keel and first chine, 1/4" thick slips, to stop the skin touching the ribs when I'm on the water.

To see if you would need an extra chine, stretch cloth over the chines and check if the cloth and ribs come within 1/2" of each other. Half inch or less, and I'd put one in. It doesn't have to contact the skin out of the water and the ends should sweep away from the skin so there isn't any hard-point where they meet.

Hope this helps,
Mike Savage
South West Cork