: OK skin boat gurus, here's something for you to chew on...

: Last weekend, I discovered that my boat is a real handful in confused chop
: and it seems that a lack of secondary stability is the culprit. It's
: really tiring just keeping the boat under me. Two days later, I paddled my
: Nordkapp for the first time since I built the skin boat and the difference
: is night and day. It is MUCH more comfortable and relaxing to paddle in
: rough conditions.

: I want my next skin boat to be somewhat different in shape (more like the
: Nordkapp) in order to increase secondary stability. For starters, I'm
: going to add a foot in length (to 18' 6"). In looking through the
: various books I have, I've noticed that many boats built by Greenlanders
: have little or no pinch in the ends. While I like the swoopy looking,
: reverse-curved gunwales from pinched ends, it seems that this really
: reduces the flare of the hull and volume at the bow and stern. I'm
: surmising that this negatively impacts stability and makes the boat a very
: wet ride. Does this make sense?

: An addtional benefit to a less pinched shape is that it increases the width
: at the foot brace, providing more foot room.

: I'm also considering moving the chine stringers in toward the keel more. I've
: read that this will decrease primary stability, but increase secondary
: stability due to more flare in the hull shape. However, I wonder if it
: actually makes the secondary stability higher or does it merely change the
: ratio of primary-secondary stability?

: Thoughts? Ideas? Wild-ass guesses?

hi brian
looks like west has it covered

but it make sense me on volume to volume that if the sheer is wider toward the ends that there more likely would be more secondary stability at this section cut. it would depend on the cg and ctr of bouyancy for the section but i think there's a good chance it would be better.

i wonder if your seat is as low as it can go. Is there anything that you can do to make it even a fraction lower.

moving the stringers is a cool idea, but moving them down will make the 2ndary worse. If you move them up, the primary will get a little worse because of the more v hull but the volume will be redistributed to the sides giving more secondary. you also will be making less verticalish chine area to side seas and maybe the chop wouldn't hit so hard.