HEIDENHAIN TNC 640, User Manual, Page: 776 / 948

Manual Operation and Setup | Presetting with a 3-D touch probe
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HEIDENHAIN | TNC 640 | Conversational Programming User's Manual | 10/2017
Circle center as preset
With this function, you can set the preset at the center of bore
holes, circular pockets, cylinders, studs, circular islands, etc.
Inside circle:
The control probes the inside wall of a circle in all four coordinate
axis directions.
For incomplete circles (circular arcs) you can choose the
appropriate probing direction.
Position the touch probe approximately in the
center of the circle
Select the touch probe function: Press the
PROBING CC
soft key
Select the soft key for the desired probing
direction
Probe: Press the
NC Start
key. The touch
probe probes the inside wall of the circle in the
selected direction. Repeat this process. After
the third probing operation, you can have the
control calculate the center (four touch points are
recommended)
Terminate the probing procedure and switch to
the evaluation menu: Press the
EVALUATE
soft
key
Preset
: Enter both coordinates of the center of
the circle in the menu window
Apply with the
SET PRESET
soft key
Further information: "Writing measured values
from the touch probe cycles to a datum table",
page 756
Further information: "Writing measured values
from the touch-probe cycles to the preset table",
page 757
To terminate the probe function, press the
END
soft key
The control needs at least three touch points to
calculate outside or inside circles, e.g. with circle
segments. More precise results are obtained with four
touch points. If possible, always pre-position the touch
probe to the center.