The aim of this case study is to implement the Lean Six Sigma methodology to reduce the scrap rate of the edge-bending process of a metal door case used in the assembly process of refrigeration appliances. This study was initiated because the assembly process of refrigerators does not work at maximum capacity due to the scrap that occurs for this component. Losses have direct effects on a company’s profits and on its competitiveness on the market. This research provides an overview of the identification of the most optimal and useful tools that can be used in each context; this will help to establish a protocol which can be applied in similar contexts. Although this study is limited to one process, the results will have direct effects on the assembly line of the organization. The purpose of this study is to increase the capability of the process and to improve the efficiency of the delivery of the component parts to the assembly line. This case study provides further evidence of the effectiveness of the use of the Six Sigma methodology in identifying and reducing scrap rates.