In the present scenario of global manufacturing, manufacturing industries are striving for quality and the cost reduction to meet customer satisfaction, market demand, and increasing productivity. Quality of a product is degree of perfection. Even product has to be manufactured according to a particular specification, regarding its dimensions, surface finish, internal structuring, etc. After production, products are inspected for verifying above parameter. The organization wants to reduce costs and improve quality by reducing variations in the process. The Taguchi DOE techniques are one of the most effective systems of off-line quality control which involve controlling the variation in a process through design of experiments. Responses are the quality characteristics of the products and processes. Signals and noises are parameters which affects the responses and they are controllable and non controllable respectively. As casting is a versatile method of manufacturing process, the processes will be study and take observation the whole journey of casted part named FAS. The main aim is optimization of hardness of FAS Part.