GMA MIG plug welds are made by aiming the electrode at what angle?

GMA MIG plug welds are made by aiming the electrode at what angle?

• A. 0°
• B. 90°
• C. 45°
• D. 135°

Answer: (B)

In MIG plug welds, the electrode is aimed perpendicular to the work surface (90 degrees). This orientation brings the arc directly into the center of the drilled hole, helping the molten metal flow evenly into the void and fuse with both plates. The result is a symmetrical plug with good penetration and full fill around the edges. Angles like 0°, 45°, or 135° would tilt the molten pool, causing uneven fill, edge buildup, or possible burn-through, and they don’t promote the same balanced fusion of both sheets.

In MIG plug welds, the electrode is aimed perpendicular to the work surface (90 degrees). This orientation brings the arc directly into the center of the drilled hole, helping the molten metal flow evenly into the void and fuse with both plates. The result is a symmetrical plug with good penetration and full fill around the edges. Angles like 0°, 45°, or 135° would tilt the molten pool, causing uneven fill, edge buildup, or possible burn-through, and they don’t promote the same balanced fusion of both sheets.