Structural modification of tool holder geometry as a chatter avoidance method

Chatter is a self-excited vibration that occurs during cutting operations such as milling, which leads to undesirable consequences such as poor surface finish and increased tool wear. The traditional approach to avoiding chatter involves experimentally determining the tool tip frequency response function (FRF) of the machine with each tool holder in place, a very time-consuming procedure. This paper proposes a new structural modification (SM) method for the optimisation of tool holder geometry. Firstly, a direct frequency domain SM method is presented, which allows the user to select an optimum tool holder geometry without any knowledge of the interface properties. Secondly, an inverse SM method is presented, which allows the user to optimise the tool holder geometry using a single experimental model and a single numerical model, again with no knowledge of the interface properties. Both the direct and inverse methods are then demonstrated using experimental data.