: With sufficient rocker you can turn a boat in it's own space. No edging or

: Agreed but since much more of my sea kayaking paddling is spent
: tracking/cruising rather than turning, especially abruptly, I don't want a
: lot of rocker.

: I've enjoyed and learned from your building posts. One thing I haven't seen
: asked is whether one can build a strip boat from strips of 4mm okoume or
: is it to flexible? Would it work if glassed on both sides? Any ideas?

I've suggested ripping strips from plywood several times. You get basically "Clear" strips with very few if any knots, and no knots going through the thickness of the strip at all. You get a nice uniform thickness, and the surface is already smooth, so no planing is needed. You save steps, time and sandpaper.

When you rip strips from a cedar board you typically get a 1/4 inch strip and a kerf of jsut under 1/8th inch. In effect you are turning a bit less than 1/3 fo your board into sawdust. with thin kerf blades that comes closer to 1/4 or 1/5th of you material as sawdust. On the other hand, if you rip 1/8th inch strips and have a 1/8th inch kerf your waste is 50%. For 3/16 inch strips the amount of waste is higher than for 1/4 inch strips, but less than for 1/8th inch strips.

Since these strips tend to be a bit rough the common practice is to cut them a bit over size and plane them to an exact thickness. This creates a bit more waste, and therefore fewer strips for your dollar. But, we all do this because they ARE beautiful strips !

When you cut 1 inch wide strips from a sheet of plywood with a 1/8th inch kerf your loss is about 12 percent. With a more "standard" 3/4 inch strip that waste would be about 17%. With a narrow kerf sawblade your waste woudl be even less.
Since you are cutting the narrow edge of the "strip" and the face pof the strip is already smooth, there is no additional waste and no additional planing is needed either for beauty, or for uniformity.

For those who use bandsaws, the total amount of wood lost to the blade is less, whether you use plywood panels or solid wood boards. But, with bandsawn strips from boards planing is practically a necessity, and you get some additional waste there. Using a bandsaw to cut strips from plywood panels (assuming you could feed the panel smoothly and straight) would be a very low waste method. Even a low power bandsaw should cut through the thin plywood like a hot knife through butter.

Plywood tends to fray and chip at the edge of a cut, however, and such chips would greatly mar the looks and usefulness of these strips. A good sharp sawblade or band, support for the wood right up to the cut, and other methods can reduce or eliminate such problems. Prescoring the plywood with a sharp knife, and precoating the plywood with a light coat of epoxy resin before cutting are other options.

A beaded edge will remove most of the sawing errors, but they show up on the cove more. So, cove the best side, bead the worst.

Is 4 mm okume too flexible to use as a material for strips? Good question. With a rounded hull the curvature of the hull tends to strengthen things. That's why a 3/16th inch strip can bend like crazy but a boat made from many of them will be stiff. I suspect the same result would be obained from using plywood strips.

In a worst case scenario, ribs or open bulkheads could be inserted inside the boat for additional support.

For a simple "Rib": An 8 foot piece of 1/16th thick and 3/4 inch wide wood could be coated on one side with epoxy and wound into a 1 foot diameter circle. Set that inside the boat and alow it to carefully expand until it comes into contact with the oval shaped interior. The wood's spring action will do most of the work of holding this strip in place until the resin hardens. When it does, you'll have a laminated-in-place rib.

the outer layer of plywood is frequently rather thin. Excessive sanding of the joints to give a rounded hull shape might go right through this veneer and reveal a rather unique looking wood grain along each strips joints. You can minimize this by using 1/2 inch wide strips.

Hope this helps.