Siemens SINUMERIK 840Di sl Programming Manual page 211

Corner rounding with axial precision using G642
G642 activates corner rounding with modal axial tolerances. Smoothing is not made within a
defined ADIS range, but the axial tolerances, defined with MD33100
$MA_COMPRESS_POS_TOL are maintained. Otherwise, the mode of operation is identical
to G641.
With G642, the rounding travel is determined on the basis of the shortest rounding travel of
all axes. This value is taken into account when generating a rounding block.
Block-internal corner rounding with G643
The maximum deviations from the precise contour when smoothing with G643 are defined
for each axis using machine data MD33100 $MA_COMPRESS_POS_TOL[...]. G643 is not
used to generate a separate rounding block, but axisspecific blockinternal rounding
movements are inserted. In the case of G643, the rounding travel of each axis may be
different .
Corner rounding with contour tolerance in G642 and G643
The expansions described below refine the response with G642 and G643 and rounding with
contour tolerance is introduced. When rounding with G642 and G643, the maximum
permissible deviations of each axis are normally specified.
MD20480 $MC_SMOOTHING_MODE can be used to configure rounding with G642 and
G643 so that instead of the axis-specific tolerances, a contour tolerance and an orientation
tolerance can be specified. In this case, the tolerance of the contour and of the orientation is
set using two independent setting data, programmed in the NC, so that setting data can be
specified differently for each block transition.
Setting data
SD42465 $SC_SMOOTH_CONTUR_TOL
This setting data is used to define the maximum tolerance for the contour when rounding.
SD42466 $SC_SMOOTH_ORI_TOL
This setting data is used to define the maximum tolerance for the contour when rounding for
the tool orientation (angle deviation).
This data is only effective if an orientation transformation is active. Very different
specifications for the contour tolerance and the tolerance of the tool orientation can only
have effect with G643.
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
5.3 Continuous-path mode (G64, G641, G642, G643, G644)
Path Action
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