Siemens SINUMERIK 840D sl Function Manual page 1471

Holder angle and clearance angle
The following figure depicts the two angles (holder angle and clearance angle) of a turning tool
with cutting edge position 3, that are necessary for describing the geometry of the tool cutting
edge. The cut direction in this example is 3, i.e. it denotes the negative Z direction (abscissa
direction for G18).
Figure 18-45 Angle and cut direction for a turning tool with cutting edge position 3
The cut direction specifies the reference direction of the holder angle. The clearance angle is
the angle measured between the inverse cut direction and the adjacent cutting edge (positive).
Holder angle and clearance angle are stored in the tool parameters $TC_DP10 or $TC_DP24.
Note
Cut direction and tool angle are relevant only in the cutting edge positions 1 to 8.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
18.7 Cutting edge data modification for tools that can be rotated
W1: Tool offset
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