What bead profile indicates a well-formed MIG weld on a patch panel?

• A. A jagged, uneven edge with heavy undercut
• B. A shallow, shiny surface with large gaps
• C. A uniform bead with consistent ripple and smooth contour
• D. A bead with deep crater cracks

Answer: (C)

A well-formed MIG weld on a patch panel is indicated by a uniform bead with consistent ripple and a smooth contour. This tells you the heat input, travel speed, and wire feed were well-controlled, producing even fusion along the edge without burning through or leaving gaps. The bead should sit flush with the panel, showing no excessive height or undercut, and the surface should look clean and continuous rather than rough or irregular. This combination is what you aim for to ensure both strength and a good cosmetic finish for the repair.

Other bead patterns point to problems: a jagged, uneven edge with heavy undercut weakens the joint and can trap corrosion; a shallow, shiny surface with large gaps means insufficient fusion and potential porosity or missed material; deep crater cracks indicate overheating or improper crater fill, which can lead to cracks as the weld cools.