The most common method to minimize aesthetic imperfections is the utilization of projection welding versus spot welding. Both are forms of resistance welding, but projection welding utilizes a formed projection on one piece to localized the weld current and minimize the resulting imperfection. While this technique will minimize the imperfections, all welding tends to leave some degree of surface imperfection. More information can be found in the Aesthetics section of A250.8 Appendix B.