The quality performance of a machined product is measured by its geometric dimensioning and tolerancing as well as its surface roughness. The surface roughness should be as smooth as possible for the same price. This geometrical property depends on the combination of the machining parameters. The most important parameters are: feed rate, spindle speed, cutting axial and radial depths. However, it is very difficult to define the optimal combination that will provide the smoother surface at lower prices [1]. One of the most important features in the manufacturing industry is to predict the surface roughness and tool life for a particular combination of machining parameters in order to choose the best combination for producing a part [2, 3]. Furthermore, it is always essential to reduce the costs for the quality required.

This work presents a study of a Taguchi design application to optimize surface quality in a CNC milling operation. A L9 orthogonal array was implemented and the ANOVA analysis were carried out to identify the significant factors affecting surface roughness as well as the determination of optimal cutting combination by seeking the best surface roughness (response) and signal-to-noise ratio.