: I moved the cockpit back on my second Walrus with excellent results,
: weathercocking was eliminated, and it still carves turns great. On my
: third one I lengthened the kayak, and kept the cockpit proportionally the
: same as the second one. This one tracks too strongly and doesn't carve as
: nice of turns. Yes, I made other mod's too. It seems like if the cockpit
: was move forward, it might help with the turning. Am I correct on this?

Mike,

I am better at paddling kayaks than designing them, so take my advice with a grain of salt. In the case of the "Petersen" kayak, the cockpit is far enough forward that the kayak is not trimmed properly, it is "bow heavy". This might indicate an error in the plans or simply a difference in the typical center of gravity between a builder of European, rather than Greenland, heritage.

I want the kayak perfectly trimmed, rather than with a bow or stern heavy bias (easier said than done). Many SOF builders that I have met, for lack of anything better, do this as more of an art, by eye and past experience. If the cockpit placement results in a non-balanced trim, you will make handling easier in some conditions, yet wreak havoc in others. Changing the handling characteristics from stiff tracking to easy turning is best achieved through changing other features of the hull design (rocker, chine placement, etc) rather than moving the cockpit to an unbalanced location. If I wanted easier turning, I would experiment with adding more rocker, and perhaps lowering the chine stringers, which would create a flatter bottom. I could be wrong, this is based on Maligiaq's advice that the racing kayaks have reduced rocker and higher chine stringers (creates a V bottom), they are very stiff tracking and difficult to turn, but very fast. There are a number of variables, such as the angle of the gunwales, that I don't have a good grasp on how changing them will affect handling. Harvey Golden has built over 30 different replicas and is still sometimes surprised by how his perceptions of how a hull will perform vary from actual practice.

Chris Cunningham gives a good method, in his Greenland SOF articles, for determining cockpit placement by measuring your balance point while seated on plank situated over a dowel.

Greg Stamer