AbstractThis article deals with the influence of cutting edge preparation and cutting edge radius on tool life, cutting forces and the roughness of machined surface. The cutting edge preparation was done on the inserts with wiper geometry which are used during machining of dividing plane at a steam turbine casing. This cutting inserts were prepared by the technology of grinding, drag finishing and laser technology. The edge radius for drag finished tools was 5, 10 and 15μm and for laser treated tool 5μm. The workpiece material was ferrite – martensite steel with the content of 9%Mo and 1%Cr and the material of cutting inserts was submicron sintered carbide. There was used only one cutting insert in the milling cutter.