UD Cantenan^s small-scale aluminum metal casting industry is a manufacturing industry that produces components and handicrafts from aluminum. The problem with this industry is that the quality of the products produced is still low. This research aims to reduce the failure rate of products by improving their quality starting from the process division of raw material preparation, casting, machining and inspection, to improving quality using the Six Sigma methodology. The quality of the product studied was a flat pulley. Data collection was carried out using a questionnaire. The research results showed that the cause of pulley product defects occurred because there had been no procedures and testing of raw materials before further processing, the melting temperature was unstable and procedures for adding additional materials (flux) had not been implemented. The most product defects occur in the casting division, namely dros (pin holes) and porous.
Keywords: Metal Casting, Aluminum, Product Quality, Defects, Six Sigma, Failure.
