A tac weld (often called a tack weld) is a temporary weld used to hold metal pieces in place before final welding. It is commonly applied in fabrication, construction, and repair work to ensure proper alignment and positioning. Tac welds are usually small, spaced points that keep components stable while allowing adjustments if needed. This technique helps reduce distortion and ensures accuracy during the full welding process. Once everything is correctly aligned, the final weld is completed over or around the tack welds. Using tac welds improves efficiency, minimizes errors, and enhances the overall strength and quality of the finished structure.