In cup walking, where should the nozzle be positioned?

• A. Directly over the groove center
• B. On both sides of the groove edges
• C. Inside the groove
• D. Away from the groove

Answer: (B)

Shielding gas coverage during cup walking is essential to protect the root bead from air contamination. Position the nozzle on both sides of the groove edges so the shielding gas blankets the weld pool and the side walls as you weave along the joint. This placement keeps the gas flow evenly distributed to both edges, preventing oxidation and porosity at the edges where they’re most vulnerable.

If the nozzle is centered directly over the groove, shielding tends to be stronger in the center but weaker at the edges, which can lead to oxidation there. If the cup is used inside the groove, gas may trap or disrupt the weld pool. If it’s kept away from the groove, the entire root is exposed to ambient air.