Tool path generation considering NC block-based machining stability

The industrial and increasing requirements of aesthetic products force the shape of product to have the complex 3D shapes. It is common to manufacture such products through three machining steps: rough machining, semi-finishing and finishing. Unlike 2.5D, rough machining step chip formation is different, depending on the tool movement in the machining process. Non-uniform chip load means unbalanced cutting force and the severe change of chip load may increase tool wear and reduce tool life. Although NC-data is generated considering machine dynamics, the irregular chip load may cause tool chatter. Especially, if the NC-data is generated without considering the dynamics of the machine tool, chatter can be created with adverse effects for the machine tool and workpiece. Thus this study proposes a methodology to analyze and generate chatter-free NC-data while maintaining the stability of the tool path. Each NC-block is divided into sections of unit-length NC-blocks and their stability is analyzed. The proposed method is validated through experimental results and is expected to improve machining productivity and quality.