Next time you're building a plywood bookcase, tabletop, or shelving unit, put down your hammer and reach for the clothes iron. That's right. An ordinary electric iron can be used to apply iron-on veneer tape to the edges of the plywood. The thin wood veneer is back-coated with a heat-sensitive adhesive. Simply lay it onto the plywood edge and press it down with a hot iron. The flexible veneer can be applied to long straight edges and to contoured pieces, such as a rounded tabletop. The veneer tape is sold through woodworking-supply catalogs and at specialty tool shops. It comes in a variety of wood species in three standard widths: 1 3/16 inches, 1 9/16 inches, and 2 inches. Prices range from 30 to 75 cents per linear foot.