Good sheet metal welding depends on the following principal factors:
(1) Preparation of the edges to be welded, including cleaning
(2) Correct procedure in the adjustment of the arc in arc welding, or adjusting the flame and using a suitable welding rod in oxyfuel welding
(3) The design of the article, the location of the welds, and the use of appropriate jigs and welding fixtures.
Resistance spot, seam or projection welding of sheet metal is commonplace, but still demands consideration of factors (1) and (3).