Siemens SINUMERIK 840D sl Operating Manual page 551

Definition of the β and γ angles
The beta and gamma angles orientate the turning tools. They refer to the WCS. If the WCS
corresponds to the MCS, the tool data remains unchanged for β=0° / γ=0° (cutter position,
holder angle, ...).
The definition of angles beta and gamma depends on the particular machine. In the initial state
of the machine kinematics for turning, a turning tool can be orientated according to Z or X.
Initial state of the machine kinematics
The tool axis is aligned in the Z direction.
β=90° represents a rotation of the cutting plate by +Y.
Mirroring
A mirroring of the Z axis (e.g. on the counter-spindle) for β=0° / γ=0° causes the same
machining in the mirrored coordinate system.
The mirroring of the Z axis must be permanently activated in a work offset.
Turning
Operating Manual, 05/2017, A5E40868721
Machine manufacturer
Please refer to the machine manufacturer's specifications.
Programming technology functions (cycles)
10.6 Further cycles and functions
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