HEIDENHAIN TNC 406 - Manual (Page 144)

HEIDENHAIN TNC 406, TNC 416 123
7.
3 Miscellaneous F
u
nctions f
o
r Cont
our
ing Beha
vior and Coor
dinat
e D
ata
7.3 Miscellaneous Functions for
Contouring Behavior and
Coordinate Data
Introduction
The following miscellaneous functions allow you to change the TNC’s
standard contouring behavior in certain situations:
„
Machining small contour steps
„ Machining open contours
„ Entering machine-referenced coordinates
„
Retracting the electrode to the block starting point at the end of
block
Machining small contour steps: M97
Standard behavior (without M97)
The TNC inserts a transition arc at outside corners. If the contour steps
are very small, however, the tool would damage the contour.
In such cases the TNC interrupts program run and generates the error
message ”Tool radius too large”.
Behavior with M97
The TNC calculates the intersection of the contour elements—as at
inside corners—and moves the tool over this point (see illustration
bottom right).
Program M97 in the same block as the outside corner.
Effect
M97 is effective only in the blocks in which it is programmed.
Example NC blocks
A corner machined with M97 will not be completely
finished. You may wish to rework the contour with a
smaller tool.
Y
X
S
Y
X
13
14
16
15
17
S
5 TOOL DEF L ... R+20 Large tool radius
...
13 L X ... Y ... R.. F .. M97 Move to contour point 13
14 L IY–0.5 .... R .. F.. Machine small contour step 13 to 14
15 L IX+100 ... Move to contour point 15
16 L IY+0.5 ... R .. F.. M97 Machine small contour step 15 to 16
17 L X .. Y ... Move to contour point 17