The cutting force increased with depend on the cut and decreasing rake angle. Explain why?

A decrease of the rake angle gives increasing cutting forces. In the insert according to the invention increasing rake angle is obtained at increasing cutting depth. This means that large cutting depths cause relatively limited cutting forces, which is often of great importance. At small cutting depth, on the other hand, the cutting force problem is not as critical, but it is more essential to decrease the rake angle in order to break the chip satisfactorily. At the corner of the insert it can often be important to have particularly great chip breaking capability. By varying the extension of the corner part and the extension of the transition area between the corner and the remaining part of the cutting edge, it is possible to vary the "severity" or effect of the chip breaking.

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