Abstract: A laser sensor to scan the weld joint before welding begins as a pre-weld scanning operation to adjust pre-programmed arc welding parameters. A “line” type laser sensor device projects a laser line within a fixed operating window. The line laser produces a reflective position of anything the laser line “sees” within the operating window. By triangulation, the exact distance an object is from the laser can be measured at any point along the “line” of the laser. Measurements of the weld bevel are stored in an electronic storage medium and a data processor. The stored measurements and data processor are used in conjunction with automated welding equipment to adjust the welding parameters as required. Because the exact joint/weld geometry is known for every portion of the weld, the welding equipment can respond or “adapt” to variations in the weld joint between the work pieces.