Page 320 - Gear Technology Solutions

Figure 17: Elimination of chip packing via back face grinding

Another additional face on bevel gear cutting blades is required if skiving as a
hard finishing operation of bevel gears is chosen. In order to optimize chip
flow, the front face of skiving blades receives a positive side rake angle of up
to 12°. However, the chip removal in skiving requires highly negative effective
rake angles. The negative cutting rake angle develops a high normal force on-
to the cutting edge, which allows the cutting edge to penetrate the hard flank
surface and start a forward moving shear crack (see also Figure 11).

Figure 18: Parameters for back face definition

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