Abstract: Plastic letter faces and letter backs are pre-cut, and a continuous edge groove or grooves are cut along the inner surface of the letter face adjacent to all edges of the letter face. A strip of plastic edge joint material is adhesively attached to a length of thin metal channel side material. The edge joint strip has a continuous groove therein for receiving the edge of a letter face and also includes a snap lock element that extends into the edge groove or grooves of the letter face when the edge of the letter face is inserted into the edge joint groove. After bending the channel side material to conform to the shape of the letter face, the edge of the letter face is inserted into the groove of the edge joint strip. The snap lock element retains the letter face edge permanently in place, allowing the partially constructed channel letter to be set aside. Later, the letter back is snap-attached to the bottom edge of the channel side of the letter.