> I built a *very* comfortable seat for my Greenland boat out of kerf-bent plywood. The method I used was:

1. Make a template for the inside curve of the seat. The seat will only curve in one dimension (a simple curve, not compound). I used a commercial plastic seat that I like and made the template follow the curve of the seat from my back, under one ischial tuberosity (sitz bone)and out underneath the hamstring of that leg. 2. Make a form out of three parallel 2x6s cut to the shape from the template, with the curve offset by the thickness of the seat you are makeing (I used 1/4" ply, so the offset is 1/2"). The 2x6s should be spaced evenly across the width of the seat. 3. Cut out two pieces of 1/4" ply. I used cheap luan. Use a tablesaw to cut kerfs in the plywood almost all the way through, spaced every half inch or so. This will make the plywood floppy and bend easily. 4. Smear both pieces with epoxy on the kerfed side and put them together, kerf-to-kerf. 5. Place the two pieces into the form and force it to take the form's shape. Nail it to the form. Use staging nails with washers to make it easy to remove. 6. After the epoxy sets, remove it from the form. Patch the holes where you nailed though. 7. Apply a layer of 'glas to each side of the seat. 8. Use a sabersaw to trim the perimeter to the shape you want. 9. Fill the edges of the ply where the kerfs show. You may want to put a strip of 'glas on the edge. 10. Apply a layer of ensolite with contact cement for padding. I find the cheap 3/8" blue foam sleeping bag pads sold in discount stores works fine. 11. Mount in the boat. You may want to mount it on rails, like most wooden seats. I suspended mine on a pivoting rod hung from the the gunwales. This allows me to flip up the seat and get at the space behind it. This boat is skin-on-frame so I don't have a rigid bottom to glue to.

I found this to give me a very comfortable seat, despite the fact that it doesn't curve from side-to-side.

Bill