311 Sculpture Surface Machining

Abstract

Ball-end milling process is used extensively in machining of free-form surfaces in automobile, die/mold and aerospace industries. A conservative selection of machining conditions for this process will avoid unwanted results such as cutter breakage or over-cut due to excessive cutter deflection, but will decrease productivity as well. In order to come up with optimal machining conditions, the prediction of cutting forces during this process is essential. These problems are particularly important for machining of sculptured surfaces where axial and radial depths of cut are abruptly changing. In this work, a mathematical model is developed for the prediction of cutting force system in ball-end milling of sculpture surfaces which calculates the cutter/workpiece intersection domain automatically for a given tool path, cutter and workpiece geometries. The model also determines the surface topography and scallop height variations along the workpiece surface which can be visualized in solid form. In this paper, predicted and experimentally measured forces as well as varying engagement domains and surface topographies are shown. The predicted and measured values are matching well.