This paper proposes a new approach to simulate 3D cutting force components generated during the finishing hobbing process of larger spur gear parts. This new approach combines three modelling steps. In the first step, the profile of the undeformed chip created for every hob’s tooth is calculated using the geometrical simulation of the gear hobbing process. In the second step, the calibration of the specific force coefficients (cutting and edge effects) is obtained from a 2D numerical model. In the final step, a mechanistic model is applied to the hobbing process. The results of this investigation are presented in terms of the analysis of the undeformed chip characteristics and the evolution of the hobbing cutting forces.