there is no reference line. It's like putting ply on a frame boat, you bend an oversized panel over the frame then attach it trimming excess. There's an opportunity to allow for variations in deck height should a person so chose to put in a tighter deck beam but I think it's oversized simply because that's how you'd do it with a big sheet of plywood. The radius isn't constant, it tends to increase at midpoint then flatten. There's a funny thing going on conceptually,,the radiused deck beam would imply that the deck shape is conical but actually the plywood would rather take a portion of a cone at the bend in the center then developing into a straighter section at the sides where the leverage on the wood lessens. You can see the difference in what I'm talking about if you look at the deck of an Arctic Hawk. The deck at the front of the coaming develops from a simple three point bend, there's no attempt to approximate a portion of a circle. On the Chesapeake the deck is put onto an actual portion of a circle at the deck beam but what happens forward from there changes a bit. A big source of tech calls was the observation that the radius of the deck beam and forward bulkhead were different,,,you'd think they should be the same. I'm not sure of the original reason for the forward bulkhead being the radius of the underside of the deck beam but I think it made for less gap filling with goop with a tighter bend. If a person wanted to get anal about getting the sheer panels to some theoretical perfection I could imagine bending the side panels on a huge bending jig,,or forms,,but it would be easier to separate out the method of attaching a deck from the development of the hull shape.

When I did my banana boat I was able to get more height out of the bow without letting the deck fold by constructing the deck with a rib down the center, and was able to get more volume by cramming a spreader stick up forward,,but at that point a light bulb went off,,,why bother?

: i don't exactly know building instructions of a new clc yak but

: short answer yes.
: my understanding is that you are given an oversized basic panel size to trim
: back to the sheerclamps after attaching - and this makes sense. but do you
: draw/get an exact profile( or say + 1/16") to use as a reference line
: to align the sheer/clamp ply edge and nail/screw to?

: what i'm saying is that if you did, and if the deck was built with constant
: radius, then the sheers would be symmetrical also.

: (their technical articles say you build with an overlap of 1 inch or so. so
: is the panel size given a constant exact 1" wider than the desired
: sheer curve?)
: if so, then i'm off base. and any errors are just building errors not process
: errors.