A method for generating tool paths for milling pockets in prismatic parts using multiple tools

Abstract

A significant amount of mechanical parts is manufactured by milling, and the process of 2.5D rough milling is responsible for removing most of the material, while the finishing stage can be performed in machines with up to 5 axes. 2.5D milling is defined as the process composed of a series of 2D paths on the XY plane at different Z levels. A high material removal helps to reduce manufacturing time, which is very important for a company to compete in today's market, where it is necessary that the manufacturing processes become faster and more flexible. The generation of tool paths for 2.5D milling is a topic of great importance in the manufacture of parts, because a large amount of mechanical parts have surfaces parallel or normal to a single plan. This work seeks to contribute to reducing the machining time by generating paths for multiple tools where a tool with a larger diameter removes as much material as possible in a short time, and subsequently smaller diameter milling tools are used to remove the remaining material. The implemented method is based on the use of Boolean operations to determine the areas to be machined. Different pockets were machined using the paths generated by the proposed method, and up to three different cutter diameters were considered. The paths generated were compared with the paths generated by a commercial software, and the following factors were considered: machining time, tool flank wear, and surface roughness.