A main requirement in the field of polymer composites milling with fibre reinforcement is to machine with high quality in one operation (without delamination or burrs). That requires precise selection of cutting tool geometry and cutting conditions. Fibre-reinforced plastics (FRPs) are difficult-to-machine materials due to high abrasivity, relatively low melting point of polymeric matrices and inclination to delamination or large burr formation. This study investigates the main factors influencing the forces, temperature and surface quality in terms of the cutting conditions through ANOVA testing. Machining during this experiment was performed with a polycrystalline diamond (PCD) end mill. Next, the strongest factor with various double-helix cutting tool geometry was compared. The geometric model of the cutting forces was created based on previous measurements as well as a general empirical model of cutting forces, temperature on the machined surface and average delamination length for C/PPS material.