HEIDENHAIN TNC 640 (34059x-05) ISO programming - Manual (Page 219)

Approaching and departing a contour 6.3
6
TNC 640 | User's ManualDIN/ISO Programming | 1/2015
219
Departing on a circular path with tangential
connection:
DEP CT
The tool moves on a circular arc from the last contour point P
E
to
the end point P
N
. The circular arc connects tangentially to the last
contour element.
Program the last contour element with the end point P
E
and
radius compensation
Initiate the dialog with the
APPR/DEP key and DEP CT soft key:
Center angle CCA of the arc
Radius R of the circular arc
If the tool should depart the workpiece in the
direction opposite to the radius compensation:
Enter R as a positive value.
If the tool should depart the workpiece in the
direction opposite to the radius compensation:
Enter R as a negative value.
R0=G40; RL=G41; RR=G42
Example NC blocks
N20 G01 Y+20 G42 F100 Last contour element: PE with radius compensation
N30 DEP CT CCA 180 R+8 F100 Center angle=180°, arc radius=8 mm
N40 G00 Z+100 M2 Retract in Z, return to block 1, end program
Departing on a circular arc tangentially connecting
the contour and a straight line: DEP LCT
The tool moves on a circular arc from the last contour point P
E
to an auxiliary point P
H
. It then moves on a straight line to the
end point P
N
. The arc is tangentially connected both to the last
contour element and to the line from P
H
to P
N
. Once these lines
are known, the radius R suffices to unambiguously define the tool
path.
Program the last contour element with the end point P
E
and
radius compensation
Initiate the dialog with the
APPR/DEP key and DEP LCT soft key:
Enter the coordinates of the end point P
N
Radius R of the circular arc. Enter R as a positive
value
R0=G40; RL=G41; RR=G42
Example NC blocks
N20 G01 Y+20 G42 F100 Last contour element: PE with radius compensation
N30 DEP LCT X+10 Y+12 R+8 F100 Coordinates PN, arc radius=8 mm
N40 G00 Z+100 M2 Retract in Z, return to block 1, end program