This paper presents a general methodology for analyzing mouldability of near-net-shaped manufactured parts based on part geometry. A freedom cone representing the aggregate of all possible instantaneous translation directions is introduced to describe geometric constraints. Using the concept of internal and external undercut, the part is divided into pockets in which freedom cones can be determined independently. Based on freedom cones, closed cavities, external undercuts and internal undercuts are identified and an optimal pair of main parting directions to minimise the number of side cores is obtained. By intersecting the freedom cones with a unit sphere, the developed algorithm can be implemented effectively on a PCbased system. The proposed methodology provides a link between part geometry and mould design and can be applied to design for mouldability (DFM) and automatic mouldability analysis in near-net-shaped manufacturing processes.