Based on problems with the Small Medium Enterprise (SME) of welding machine services. The Manual Metal Arch welding machine produced has a complex design, which causes high production prices and makes it uncompetitive in the market. Based on this issue, we need to analyze, redesign, and estimate assembly costs using the Design for Manufacture and Assembly (DFMA) approach, which will increase quality and reduce assembly costs. This research produces a new design using Acrylonitrile Butadiene Styrene (ABS) material. ABS has a better dielectric constant than sheet metal carbon steel, it can increase user safety. The use of ABS can reduce 54.39% of the number of components from 57 to 26 parts and reduce 36.16% of the total weight from 4013 to 2562 g. It is easier for user mobility. In addition, the use of DFMA methods can reduce 53.61% assembly time from 477.71 to 221.61 seconds, reduce 0 …