Copy Mills Widia M270 Series Additional Application Advice M270 Ball Nose Calculating effective diameter and resulting surface speed It is importan

Copy Mills Widia M270 Series Additional Application Advice M270 Ball Nose Calculating effective diameter and resulting surface speed It is important to consider the effective diameter (Deff) when using light depths of cut in order to properly calculate RPM values. Use the following formula when machining flat surfaces or inclinations of 10° or less to find the Deff value, and then use this for RPM calculations as opposed to using the overall insert diameter (D1). When machining inclinations between 11° and 55°, further modification of vc is required. Apply factor k from the given formula to calculate the correct vc (vceff). This corrected value is then used to calculate the proper RPM for the tool. Deff VD12-(D1-2Ap1)2 sin a + arcCos (1-(2 (Ap1/D1))) v eff v X k c c Starting Values for Semi-Finishing in Common Material Types (L/D ratio <3 x D1) M270 is usually applied for semi-finishing and finishing operations; Ap1/ae conditions depend on the operation. As a general rule Ap1/ae s0,05D. 1 k Material Tool Diameter 010 012 016 020 025 032 max rec. (mm) fz (mm/ tooth) max rec. (mm) fz (mm/ tooth) max rec. (mm) fz (mm/ tooth) max rec. (mm) fz (mm/ tooth) max rec. (mm) fz (mm/ tooth) max rec. (mm) fz (mm/ tooth) Ap1 ae Ap1 ae Ap1 ae Ap1 ae Ap1 ae Ap1 ae Soft Steel <250 HB 0,7 0,7 0,2 0,8 0,8 0,2 1,1 1,1 0,27 1,3 1,3 0,27 1,7 1,7 0,3 2,1 2,1 0,3 High-Strength Steel 33-44 HRC 0,5 0,5 0,15 0,6 0,6 0,2 0,8 0,8 0,25 1 1 0,25 1,3 1,3 0,25 1,6 1,6 0,25 Hardened Steel 44-55 HRC 0,3 0,3 0,15 0,4 0,4 0,2 0,5 0,5 0,22 0,7 0,7 0,22 0,8 0,8 0,25 1,1 1,1 0,25 Grey Cast Iron GG25 1 1 0,2 1,2 1,2 0,25 1,6 1,6 0,25 2 2 0,25 2,5 2,5 0,3 3,2 3,2 0,3 Nodular Cast Iron GGG60 0,7 0,7 0,2 0,8 0,8 0,25 1,1 1,1 0,25 1,3 1,3 0,25 1,7 1,7 0,3 2,1 2,1 0,3