Five axis milling allows to machine free form surfaces with cylindrical or toric cutters instead of ball nose cutter. This drastically reduces the machining time. Commercial CAM modules however require the NC-programmer to specify the appropriate inclination of the tool with respect to the work piece surface normal. This is difficult especially for complex parts with vaving surface curvature. This paper presents five axis CAM software which vanes the tool inclination during the tool path generation, in order to achieve the best combination of scallop height, workpiece accuracy, surface roughness and machining cost. Machining time to produce some free form workpieces, given a maximum scallop height, could be reduced by 50%.