Siemens Sinumerik 840D sl Programming Manual page 279

Note
The approach behavior is symmetrical to the retraction behavior.
The approach/retraction behavior is determined by the state of the G command in the approach/
retraction block. The approach behavior can therefore be set independently of the retraction
behavior.
Examples
Example 1: Retraction behavior with G460
The following example describes only the situation for deactivation of tool radius
compensation: The behavior for approach is exactly the same.
Program code
G42 D1 T1
...
G1 X110 Y0
N10 X0
N20 Y10
N30 G40 X50 Y50
Example 2: Approach with G461
Program code
N10 $TC_DP1[1,1]=120
N20 $TC_DP6[1,1]=10
N30 X0 Y0 F10000 T1 D1
N40 Y20
N50 G42 X50 Y5 G461
N60 Y0 F600
N70 X30
N80 X20 Y-5
N90 X0 Y0 G40
N100 M30
Further information
G461
If no intersection is possible between the last TRC block and a preceding block, the offset
curve of this block is extended with a circle whose center point lies at the end point of the
uncorrected block and whose radius is equal to the tool radius.
The control attempts to cut this circle with one of the preceding blocks.
Fundamentals
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Comment
; Tool radius 20 mm
Comment
; Milling tool type
;Tool radius
Tool radius compensation
11.4 Smooth approach and retraction
279