: build a guillemot 17' with 21 inch beam. love design and handling
: wwould like to build another but with a min 27 " beam.
: tendom would take care of beam with but would lose
: sleaknness!!!! any idea how to modify etc? I'm a short heavy man
: at 5'8 240# need the width.

You can stretch a kayak lengthwise by stretching out the spacing between forms, but going wider is a whole different geometry. There is no easy way to do it, and you are risking changing the cg of the boat as well. I would suggest looking for something readily available in the dimensions you want, but fyi you won't find 27". Maybe you need to look into a decked canoe. Even 24" is wide for a kayak, and one inch makes a much bigger difference than one might think.

You might want to look at Ian Oughtred's "MacGregor" sailing canoe. It has plans designed for lapstrake plywood construction that can be modified for strip. (Both lines are on the station molds.) I don't remember the width, but it's kind of a cross between a wide kayak and a narrow canoe. It can easily be double-paddled and comes with a plan for a sloop and yawl sailing rig. It can be built in three lengths from 13.5 feet to 17.5 feet by stretching out the form spacing. Ian Oughtred is a master designer and has drawn some of the most beautiful boats on the water. I highly recommend doing it in lapstrake ply as designed (the lines of the lapstrake are gorgeous) but again you can strip it just as well. You could deck it as planned and have room for two or three people or you could put more deck and make it into a very large kayak. Remember, even if you deck it for two people you could still put a large custom-made sprayskirt on it. It will not, however, handle like a kayak. It's more of a flatwater boat so if you are looking to ocean paddle I do not recommend the MacGregor. For lakes and streams and small rivers it is perfect.

Good luck!

Malcolm