Cozy Boat

Step 7 Closed-Cell Foam

I put an inch of soft closed-cell foam between the frame and the skin. It serves a number of functions. If you hit a rock the frame won't bite a hole in the skin. It makes the boat float pretty high even if it's swamped. If it gets punctured it's self-healing. This foam is what they shove between the girders of curtainwall buildings. I think it's urethane about 3lbs/cubic foot. It's similar to what they use for sleeping pads for camping. What this foam doesn't do is make you comfortable, since the ribs and stringers are between it and you. So I made a thicker closed-cell mattress to lay on the bottom and cushion the ribs.

I glued the closed-cell foam layer together using contact cement following the directions on the can. It's DAP Weldwood original earthwrecking contact cement. Fabulous stuff unless you're a brain cell.