I made a large panel from strips to make bulkheads for my strip project. I noticed how strong the flimsy panel became after I glassed both sides. This was a very good demonstration of how the fiberglass sepatated by the 3/16 wood resisted bending after being bonded into a unit. Nick Schade has a nice write-up on this in his books where he compares the new structure to an "I Beam".

The fact is that the fiberglass alone is very flexible and has little strength on its own. Unless you significantly thicken the glass layer with woven roving (like my 18' runabout) or a middle layer of foam or better yet, cedar, you won't have any strength. Adding roving (and resin) to the glass cloth weighs a lot.

The lightest kayak you are ever going to be able to build is a SOF using lightweight cedar or other light woods for the frame and lightweight cloth (nylon,etc) waterproofed with a paint product. To avoid the frame that interferes with your interior volume, the next best solution (weight wise) is a fiberglass cloth covered cedar strip boat. SOF and Strip boats of the same design can be very light with the strip boat weighing only 8-12 lbs more if you build very carefully.

I love hearing and thinking through new ideas about building but think a fiberglass cloth shell made over the frame of a SOF design fails to meet the strength test without reinforcement that reinforcement would make it fail the weigh test.

SOF and Strip are well proven light weight construction methods.... I'm building a 17' Spring Run that is ready for varnish and is weighing in at 33lbs. That's with 2 layers of 6oz cloth on most of the bottom and a double layer around the cockpit and hatch openings. Should weigh less than 40 fully rigged.... Compare that to my 14' Dagger Alcemy rec/touring boat that weighs 53lbs.

Bob Beaullieu