Chapter 8 Gas Metal and Flux Cored Arc Welding 227 Copyright Goodheart-Willcox Co., Inc. It may point more toward the surface if the edge melts too quickly. Use a backhand, forehand, or perpendicu- lar gun angle as necessary based on the metal thickness. The backhand method provides the best penetration. A drag travel angle of 15°–25° provides good control and penetration. The typical C-shaped weld pool indicates that both the edge and surface are melting properly. 8.11.2 Fillet Weld on a T- or Inside Corner Joint The majority of T- and inside corner joints are welded on a square groove weld joint. There is no joint prepara- tion other than cleaning the base metal. When greater penetration is required, a prepared groove joint can be made prior to making the fi llet weld. The electrode should be held at a 45° work angle. Aiming the wire more toward the vertical surface may improve the bead shape. This helps compensate for the molten metal sag. For the best penetration and weld pool control, use a 15°–25° drag travel angle. On thin metals, use a 15°–25° push travel angle. See Figure 8-57 for gun angles. Figure 8-58 shows a completed weld. Short circuiting, globular, spray, or pulsed spray transfer methods can be used for GMAW welding hor- izontal fi llet welds. Horizontal butt joints are limited to short circuiting and pulsed spray transfer. Trying to use the globular or spray transfer method results in a weld pool that is too large and fl uid to manage. Also, in the horizontal welding position, metal trans- ferred in globular form will not fall into the center of the weld pool. It falls straight down due to gravity. Any FCAW electrode can be used for a horizontal fi l- let weld. Only FCAW electrodes designated for all weld- ing positions can be used to weld horizontal butt joints. 8.11.1 Fillet Weld on a Lap Joint For practice welds, the metal should be set up and tack welded as shown in Figure 8-56. The centerline of the elec- trode should be about 45° to the edge and metal surface. Direction of travel 15°–25° travel angle Goodheart-Willcox Publisher Figure 8-55. A bevel-groove weld on an outside corner joint in the flat welding position. 45° from surface Tack weld 15°–25° travel angle Direction of travel Weld face is vertical or near-vertical Centerline of weld axis is near-horizontal Goodheart-Willcox Publisher Figure 8-56. A fillet weld on a lap joint in the horizontal welding position. In the horizontal welding position, the weld axis is near-horizontal and the face of the weld near-vertical. 15°–25° travel angle 45° work angle Direction of travel 45° from surface Goodheart-Willcox Publisher Figure 8-57. A fillet weld on a T-joint in the horizontal welding position. Note the angles from the metal and in the direction of travel. Goodheart-Willcox Publisher Figure 8-58. A completed fillet weld.