Rust Lap Weld

While a lap weld, created by welding two overlapping pieces of steel (not shown), makes for relatively quick setup and a strong weld, it's not always the best choice when you want your repair to disappear. Factory spot welds can be replicated by punching holes and then filling in with a plug weld (top). Butt welds will make your repair disappear, but additional prep and finish work is required (top). Ideally your gap between pieces will be approximately the width of your MIG wire or less--this will prevent distortion. Start by skipping or stitch welding (bottom left), which will keep heat-induced distortion to a minimum. After alternately welding and grinding, your joint should look like the ground area in the bottom right panel.

1989 Pontiac Formula - Corrosion Cure

While a lap weld, created by welding two overlapping pieces of steel (not shown), makes for relatively quick setup and a strong weld, it's not always the best choice when you want your repair to disappear. Factory spot welds can be replicated by punching holes and then filling in with a plug weld (top). Butt welds will make your repair disappear, but additional prep and finish work is required (top). Ideally your gap between pieces will be approximately the width of your MIG wire or less--this will prevent distortion. Start by skipping or stitch welding (bottom left), which will keep heat-induced distortion to a minimum. After alternately welding and grinding, your joint should look like the ground area in the bottom right panel. View Related Article

Rust Lap Weld

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