Siemens SINUMERIK 840DE Programming Manual page 33

These components can be used individually or in any combination.
Mirroring of the Z axis
Shifting and turning the workpiece coordinate system
One way of machining inclined contours is to use appropriate fixtures to align the workpiece
parallel to the machine axes.
... Another way is to generate a coordinate system, which is oriented to the workpiece. The
coordinate system can be moved and/or rotated with programmable frames.
This enables you to
• move the zero point to any position on the workpiece
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
Fundamental Geometrical Principles
1.3 Position of coordinate systems
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