A prototype connector has a section in the general shape of the letter. "C", thereby causing it to have a convex outer surface. Ends of the prototype connector form lips that are contiguously connected through respective flanges to ends of a web. A connector for making a butt connection between two cement composite panels is formed by two prototype connectors that have outer surfaces of their webs welded together. A connector for making an "L" connection between the two panels is formed by welding an outer surface of a flange of one prototype connector to an outer surface of a web of another prototype connector. A connector for connecting the two panels together at a preselected angle is made by using two sheet metal plates to connect each flange of a first prototype connector to a flange of a second prototype connector. A connector for making an "X" connection between four cement composite panels is made by welding outer surfaces of flanges of a first two prototype connectors to outer surfaces of webs of a second two prototype connectors in a manner that causes the outer surfaces of the webs of the four prototype connectors to define a rectangle.