Improvement of the accuracy in the machining of a deep shoulder cut by end milling

Machining accuracy has been improved with the development of NC machine tools and cutting tools. However, it is difficult to obtain a high degree of accuracy when machining a deep pocket with a long end mill, since machining accuracy is mainly dependant on the stiffness of the cutting tool. To improve surface accuracy in machining a deep pocket using an end mill, the performance by down milling and up milling is compared theoretically and experimentally. To verify the usefulness of up milling, various experiments were carried out. As a result, it is found that up milling produces a more accurate surface than down milling in the machining of a deep pocket. By applying various values of helix angle, number of teeth, radial depth of cut and axial depth of cut to experiments, effective cutting conditions in up milling are suggested.