Modelling and optimisation of up-and down-milling processes for a representative pocket feature

This paper presents the specifics of the two types of end-milling, up- and down-milling, in the context of process planning of a finishing operation for machining complex pocket features. An optimisation mechanism is used for a pocket type of end-milling operation with the aim of comparing the results from up- and down-milling. Two sets of cutting conditions have been generated and analysed for each type of end-milling-one with constant parameters for the entire tool path, derived from the worst case of cutting (representing the usual process planning approach) and another set representing the optimised process. The predicted results were verified through experiments. The optimized cutting parameters, when machining the critical corner, demonstrate the important changes in magnitude and direction of the radial cutting-tool deviation and surface error.