5-Axis Control Machining with Top and Side Cutting Edges of Ball End Mill.

5-axis control machining is usually carried out by use of either top cutting edge or side cutting edge of tool. The spherical cutting edge of ball end mill as the top cut allows to form almost any kind of shape, however, sometimes shows low surface roughness and efficiency in comparison with the side cut. Thus, the study presents the development of a new machining method using both top cut and side cut continuously, taking account of advantages of respective cutting manner. In this machining, the side cut is preferentially employed in the light of cutting efficiency since the amount of pickfeed can generally be set larger than the top cut when the cusp height on workpiece surface is kept constant. The side cut is continuously changed to the top cut when the side cut can not cope with workpieces having such surfaces as concave and/or overhanging ones. The control program developed on the basis of the above concept generates collision-free tool path which is converted to actual NC data by the post-processor. From two kinds of cutting experiments, it is found that the method proposed is valid for 5-axis control machining.