Copyright Goodheart-Willcox Co., Inc. 134 Gas Tungsten Arc Welding Handbook amount of material at the right place at exactly the right time. A 10°–20° entrance angle of the rod into the weld pool should always be maintained. Types of Beads/Passes Welds made without any side-to-side movement (oscillation) of the torch are called stringer beads, or stringer passes. Welds made with side-to-side move- ment of the torch are called weave beads. When a weave bead is being made, fi ller metal should be added at the edges of the weld pool to prevent under- cutting. Figure 8-10 compares a stringer bead and a weave bead. A technique known as walking (rocking) the cup is commonly used to create a weave pattern in V-groove butt joints in thicker sections of material. In this oscillation technique, the cup of the torch is set on the base metal. Alternating sides of the cup support the torch as the opposite side is rocked forward, much the way a refrigerator is moved across the fl oor. Walking or rocking the cup to make a weave pattern takes a great deal of practice and determination. A B Figure 8-8. The proper work and travel angles for making fillet welds. A—Proper angles for T-joints and inside corner joints. B—Proper angles for lap joints. (Mark Prosser) Figure 8-9. Welding rod held in this manner can be added to the weld pool as needed. (Mark Prosser) A B Figure 8-10. A stringer bead (A) is narrower than a weave bead (B). (Mark Prosser)