In SMAW, arc blow is minimized by using which current?

• A. Direct current (DC)
• B. Pulsed current
• C. Alternating current (AC)
• D. Constant current (CC)

Answer: (C)

Arc blow happens when the magnetic field generated by the welding current interacts with the surrounding metal and ground path, pushing the arc off the joint and causing wandering welds. Using direct current creates a steady magnetic field in one direction, which tends to bias the arc and make arc blow more noticeable. Alternating current, on the other hand, reverses polarity every half cycle, so the magnetic field also reverses direction repeatedly. These reversals cancel out over a full cycle, reducing the net sideways force on the arc. As a result, the arc stays closer to the joint and is less prone to wandering, which is why alternating current is the best choice for minimizing arc blow in SMAW.