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TNC 426/TNC 425/TNC 415 B/TNC 407
5 - 4 0
5
Programming Tool Movements
Fig. 5.49:
Machine datum
and workpiece datum
M Functions for Contouring Behavior
X
Z
Y
Y
X
Z
M
M
M
.
.
.
Workpiece datum
The user enters the coordinates of the datum for
workpiece machining in the MANUAL OPERATION
mode (see page 2-7).
If you want the coordinates to always be
referenced to the machine datum or to the
additional machine datum, you can inhibit datum
setting for one or more axes.
If datum setting is inhibited for all axes, the TNC no
longer displays the DATUM SET soft key in the
MANUAL OPERATION mode.
Feed rate factor for plunging movements: M103 F…
Standard behavior – without M103 F…
The TNC moves the tool at the last programmed feed rate, regardless of
the direction of traverse.
Reducing the feed rate during plunging – with M103 F…
The TNC reduces the feed rate for movement in the negative direction of
the tool axis to a given percentage of the last programmed feed rate:
F
ZMAX
=
F
PROG
∗
F
%
F
ZMAX
:
Maximum feed rate in negative tool axis direction
F
PROG
:
Last programmed feed rate
F
%
:
Programmed factor behind M103, in %
Cancelling
M103 F… is canceled by entering M103 without a factor.
Example
Feed rate for plunging is to be 20% of the feed rate in the plane
Actual contouring feed rate
[mm/min]
with override 100%
G01 G41 X+20 Y+20 F500 M103 F20
500
Y+50
500
G91 Z–2.5
100
Y+5 Z–5
367
X+50
500
G90 Z+5
500
M103 F... is activated with machine parameter 7440 (see page 11-13).