Well done Dan, the scribing process you did is the way to do the job. The resulting curve on the deck is complex because of the intersection of the cone shape of the carbon recess and the compound curve of the deck. I can't think of any other way of deriving the curve other than using the actual cone to project it as you have done.

You may know this already, but just in case, I will mention that when you do the deck, the most important two elements in the scribing process are to make sure that the carbon recess unit is held rigidly still, in the exact orientation that you want to install it, and to keep the scriber consistently level, that is with the marking point of the pencil directly below the contact point on the recess surface. In essence, you are projecting the contact point straight down onto the surface of the kayak, simulating what will happen when you drop the recess into its waiting hole. When log house builders use a scriber to fit logs to one another, the scriber unit actually has two level bubbles in it to ensure that the contact point and the marker point remain absolutely vertical from one another.

Once the hole is cut, you can finesse the fit by sanding the hole edge, then sit your recess unit in the hole, trace the hole outline onto it, and cut it to shape. (all assuming that I understand what you have in mind :) )

Best regards,

Allan Edie

: Inviting critiques and advice on my recess test. Not sure why but
: the circle and the oval racked my brain all weekend. I read the
: instructions several times then had the ah ha moment. The
: instructions were clear but the geometry synapses in my brain
: refused to fire. Not willing to make my first attempt on the
: actual deck I made a mock up and the results were pretty close.

: Here's a link to the photos http://tinyurl.com/recesstest1

: A two holer :)