When building the channel iron hinge, cut a hole in the channel and weld the pipe sleeve to the bottom of the channel. The gate must not pivot against the welding bead. Weld the bottom 3-inch (8cm) wide channel gate to the gatepost. The pipe that forms the gate frame will fit over the 2-inch (5cm) pipe sleeve welded to the channel iron. The top hinge is made the same way as the bottom hinge except it is inverted, and the pipe sleeve is inserted into the top of the gate frame.