As the name suggests, a skin on frame boat consists of a wooden frame covered with a skin. While thousands of years ago hulls made of driftwood and bone were covered with seal skin, nowadays it's materials are found mainly in the lumber trade. Steam bent ribs give a skin-on-frame-boat it's shape, nylon, polyester or cotton form the skin.
Skin on Frame boats are lightweight and durable, can be built in a relatively resource efficient manner, offer a lot of craftsmanship and many different techniques for the interested canoebuilder.
Traditional construction methods do not require glue, screws or nails, as the boats are lashed together with traditional joinery and artificial sinew. More modern approaches, so-called fuselage frame boats are reminiscent of traditional aircraft construction.
Industrially manufactured boats also often feature the more angular shapes of traditional skin on frame boats, which is particularly indicative of their mature form. In contrast, hand-built boats are naturally designed to fit the body dimensions of the paddler. Although many factory-built kayaks are made in traditional sea kayak shapes, the angular and delicate look of a SOF boat is a rarity and attracts many looks.
SOFi - Frame before skinning