The cutting force dynamics in alloyed steel, stainless steel and cast iron have been investigated, although a direct measurement of the cutting forces could not be carried out. Usually, the response of the tool holder shank is measured by strain gauges and will be dependent on the stochastic character of the applied load and the structural dynamic properties of the tool holder. The characterisation of the dynamic response of the tool holder shank relies here on a stochastic approach while the structural dynamic properties were evaluated by a normal mode analysis. The results from both the analysis and the experiments correlate well.