I've read Nick's book front to back 6 times. I did the lofting for the Guillemot. Then I copied the half diagrams on a Xerox photocopier in my office, flipping each diagram to get the mirror image.
Problem: As the forms got bigger (#7, 8, 9) I turned the diagrams 90 degrees to fit on legal, then ledger size paper. I wasn't consistent, e.g. for form 9 the right side was made on the copier 90 degrees from the left side. Shouldn't matter, right? Well it does on my copier: although copied at the copier 100% setting, it turns out that the x axis is slightly larger than 100% compared to the y axis, probably to eliminate a dark left edge. I discovered this after my "mirror images" didn't line up when copied at 90 degrees to each other. The difference was about 1/8, so I split the difference. Proceeded to glue the diagrams to my plywood, cut them all out with a jig saw. But that difference bothered me, so I checked all my forms. Low and behold, every form is slightly larger at the x axis (1/8 of inch on average) at the SWL. I've tried using a hand held electric planer to knock off the excess (I traced the true line from each original loft diagram onto the glued "copies"), with inconsistent results. On each form, I am too large by 1/16 to 1/8.

My question: Must I retrace and recut all of my forms, or am I o.k. at these tolerances? I know the boat will float, but am I within suitable tolerances to proceed--given that the kayak will be planed and sanded fair?