Machining Corners - HEIDENHAIN TNC 370 User Manual

4 Programming
4.3 Tool Compensation Values
Shortening or lengthening single-axis movements R+, R-
This type of radius compensation is possible only for single-axis move-
ments in the working plane: The programmed tool path is shortened (R-)
or lengthened (R+) by the tool radius.
d
Applications:
l
Single-axis machining
l
Occasionally for pre-positioning the tool, such as for the SLOT MILLING
cycle.
* A+ and R- am svaifabfe whenever B positioning
black
is craated with the soft key for axis X, Y, Z w IV.
* Tha machine tool builder can set. a machine par-am&r b inhibit such single-axis positioning l&&s.
Machining corners
If yx.~ work without radius compansatian, yau can influence the machining of otisido ~33n-t~~ with the
miscelianeous funcW7 M9Q fkw3 page 5-51).
Outside corners
The control moves the tool in a transitional arc
around outside corners. The tool "rolls around" the
corner point.
If necessary, the feed rate F is automatically
reduced at outside corners to reduce machine
strain, for example for very sharp changes in
direction.
Inside corners
Fig. 4.10: The tool "rolls around" outside corners
To prevent the tool from damaging the contour, be sure WI to program the starting (or endf pcx&tions for machining
inside cofners at a ccxnef of the contour.
The control calculates the intersection of the tool
center paths at inside corners. From this point it
then starts the next contour element. This prevents
damage to the workpiece at inside corners.
When two or more inside corners adjoin, the
chosen tool radius must be small enough to fit in
the programmed contour.
Fig. 4.11: Tool path for inside corners
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