> In the December "Sea Kayaker" there's an article about building
> the CLC West River 180, with the plans and steps and so on.

> At a point in the process before the hull is glassed, a photo caption
> says, "When the hull is resting on two level sawhorses use a string
> to check that you have 2" of rocker." I couldn't find any other
> mention concerning this, so my question is:

> Where, and how, if appropriate, is rocker measured?

> - Where the keel starts to actually turn up at the bow or stern?

> - Where the tangent to that curve goes through a 45 degree angle to level?

> - At the imaginary intersection of the straight line extensions of the
> keel with the stems?

> - Where the waterline is at any given displacement at the bow and stern?

> - Somewhere else?

> In the Pygmy kits the measurement is made at measured distances from a
> specified location on the keel line, i.e., "x" inches fore and
> aft of the middle butt seam, but here in the West River that location can
> vary depending on the scarf work, and in any event it isn't specified.

> Any thoughts?

Not being very experienced at boat building but having done 3 skin on frame kayaks, I also asked myself the very same questions.

In technical terms I've felt that the rocker would be measured at the intersection point where the stem or stern line meets a tangent line to the keel line. Practically it is difficult and probably unnecessary to work to this point except when dealing with drawings. Practically the rocker can be measured at the end of the keel where the curve to the stem or stern starts. The error when dealing with flat rockers will be very small.

Bram