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Re: Rocker Measurement: Where?
By:Dean Trexel
Date: 11/19/1999, 11:46 pm
In Response To: Rocker Measurement: Where? (Pete Roszyk)

My guess is that this is measured at the tip of the lowest hull panels. The other hull panels really form more of the vertical bow line.

I think that the rocker can vary, though. If you stitch the two lower hull panels together, then lift one end, the rocker will vary and the panels will change angle with respect to each other as the curve of their joint changes. If the West River 180 was designed to spring around just the 2 bulkheads (I'm not sure on that) then there aren't a whole lot of constraints on the hull's shape and verifying the rocker is probably not a bad idea...

Dean

> 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?

Messages In This Thread

Rocker Measurement: Where?
Pete Roszyk -- 11/18/1999, 3:13 pm
Re: Rocker Measurement: Where?
Bram -- 11/20/1999, 12:00 pm
Re: Rocker Measurement: Where?
Dean Trexel -- 11/19/1999, 11:46 pm
Re: Rocker Measurement: Where?
lee -- 11/18/1999, 8:44 pm