Siemens Sinumerik 840D sl Programming Manual page 75

If the term "drill" is used in this Chapter, it refers only to the working cycle that are executed
with the help of fixed cycles, even though naturally there are fixed cycles for tapping, boring
or drilling cycles too.
Definition of the current plane
In drilling cycles, one generally assumes that the current coordinate system in which the
machining operation is to be executed, is defined through the selection of plane G17, G18 or
G19 and activation of a programmable work offset. Drilling axis is then always the application
of this coordinate system.
Before calling the cycle, one must always select a tool length compensation. It is always
effective perpendicular to the selected plane and remains active even beyond the end of the
cycle.
Table 4- 2
G function
G17
G18
G19
Xp: X axis or an axis parallel to the X axis
Yp: Y axis or an axis parallel to the Y axis
Zp: Z axis or an axis parallel to the Z axis
Note
Whether the Z axis should always be used as the drilling axis can be defined with GUD7,
setting data _ZSFI[0]. The Z axis is then always the drilling axis, if _ZSFI[0] is equal to "1".
ISO Milling
Programming Manual, 06/09, 6FC5398-7BP10-1BA0
Positioning plane and drilling axis
Positioning plane
Xp-Yp plane
Zp-Xp plane
Yp-Zp plane
Additional functions
4.1 Program supporting functions
Drilling axis
Zp
Yp
Xp
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