> Thanks for the the comments, very useful.
> I want to build an 18' Guillemot for a little extra space for camping. I
> live in BC and Vancouver Island has amazing 1-3 week routes (check out
> Tofino area sometime). I have only just begun lofting the forms and my
> wood won't arrive until mid December. In Nick's book he has a 19' version
> which I assume he added an extra form. I think that I should be OK by just
> increasing the spacing of the forms to acheive an overall length of 18',
> if this is a plan that I'll later regret comments are welcome. The 19'
> Guillemot has the same width of 21" as the 17', so this looks to me
> that stretching it out to 18' will not effect the Kayaks handling.
> It is good to see there is a forum to ask question while I'm building, the
> sharing of ideas is helpful. That link for time-frame is excellent!
> Sean

Although Nick's book recommends extreme care when modifying his existing designs, I believe you should be able to insert an additional station right in the center. I'd choose the form with the lowest point along the hull centerline which should be somewhere in the cockpit area. The hull cross-section doesn't change shape too drastically from station-to-station in that area, so you may be able to get away with two exact duplicate stations. However, you won't be able to verify that it will produce a fair hull until you've got all the stations anchored to the box beam and you can finally lay a couple test strips along the hull. At that point, you may have to shave or shim your additional station to produce a fair curve.

On a related note, I made my box beam out of 1/2" plywood, which turned out to be too thin of material. The beam would flex and bow if it wasn't mounted to sawhorses. Perhaps it was the type of plywood I used, but next time I'll definitely go with something heavier. Because the box beam had so much flex, I decided to align the forms upside down to begin with so I wouldn't have to flip it over after they were aligned and risk having to go through the alignment process twice. I slid all the forms into the correct locations and then anchored the box beam to the sawhorses. Once the hull is stripped, the whole boat will be rigid enough to flip over without messing-up the alignment.