Additional Application Advice • M270 Ball Nose

Selecting the Correct Insert and Cutting Conditions for Your Application

1. Insert Style: Considerations for Selecting the Correct Insert

BR GeometryBF Geometry
Best Choices for Insert and Grade Selection
�First choice �Alternate choice
GradeTN7535TN2510TN2505
Roughing Operation
Finishing Operation
Low RPM Machine
Flat Areas or Face Milling (≤10° inclination)
Hard Machining
Unstable and/or Long Overhangs
HSM or 5-Axis Machining (smaller ap/ae values)

2. Calculating effective diameter and resulting surface speed

It is important to consider the effectiveWhen machining inclinations between
diameter (Deff) when using light depths11° and 55°, further modifi cation of vc
of cut in order to properly calculate RPMis required. Apply factor “k” from the
values. Use the following formula whengiven formula to calculate the correct
α
machining fl at surfaces or inclinationsvc (vceff). This corrected value is then
of 10° or less to fi nd the Deff value,used to calculate the proper RPM for
Ap1
and then use this for RPM calculationsthe tool.
as opposed to using the overall insert
diameter (D1).
DD
effeff
DD
11
1
k =] [α

Deff 2-(D1-2Ap1)2 sin + 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-fi nishing and fi nishing operations; Ap1/ae conditions depend on the operation. As a general rule: Ap1/ae )0,05D.

Tool Diameter

Ø10 Ø12 Ø16 Ø20 Ø25 Ø32

Tool Diameter
Ø10Ø12Ø16Ø20Ø25Ø32
max (mrec. m)fz (mm/max (mrec. m)fz (mm/max (mrec. m)fz (mm/max (mrec. m)fz (mm/max (mrec. m)fz (mm/max (mrec. m)fz (mm/
MaterialAp1aetooth)Ap1aetooth)Ap1aetooth)Ap1aetooth)Ap1aetooth)Ap1aetooth)
Soft Steel0,70,70,20,80,80,21,11,10,271,31,30,271,71,70,32,12,10,3
High-Strength Steel 33–44 HRC0,50,50,150,60,60,20,80,80,25110,251,31,30,251,61,60,25
Hardened Steel 44–55 HRC0,30,30,150,40,40,20,50,50,220,70,70,220,80,80,251,11,10,25
Grey Cast Iron GG25…110,21,21,20,251,61,60,25220,252,52,50,33,23,20,3
Nodular Cast Iron GGG60…0,70,70,20,80,80,251,11,10,251,31,30,251,71,70,32,12,10,3