TurningMillingDrillingTechnicalInformationIndex Technical information – turning Technical information Turning toolsCutting time Tc for face milling A π × (a2− b2) TC = [min] 4000 × Vc × f Tc: Cutting time [min] Vc: Cutting speed [m/min] f: Feed rate [mm] B Theoretical surface roughness R f2 R= 8rc ×1000 [μm] C R: Surface roughness [μm] f: Feed rate [mm] rc: Radius of insert [mm] Example: f = 0,2 mm, rc = 0,4 mm D E A 453