The quality of a machined surface can be described by macro and micro parameters, like the size error, the form and position error or the surface roughness. The task of machining process planning is to find the best machining method and parameters, which ensure the required quality. In this article, the surface roughness in the case of turning and milling technologies is analysed. The effect of the cutting parameters (feed at turning and depth of cut at milling) and the tool parameter (corner

more »

... dius) are investigated. The results are compared with the theoretical geometric model of surface roughness. In longitudinal turning as well as in constant Z-level milling, the geometric model of surface roughness is similar. The article presents whether the real surface roughness is similar too.