HEIDENHAIN TNC 620 User Manual page 511

14.6 Datum setting without a 3-D touch
probe
Note
When you set a datum, you set the TNC display to the coordinates
of a known workpiece position.
All manual probe functions are available with a 3-D
touch probe.
Further Information:
touch probe (option number 17)", page 533
Preparation
Clamp and align the workpiece
Insert the zero tool with known radius into the spindle
Ensure that the TNC is showing the actual positions
Datum setting with an end mill
Protective measure
If the workpiece surface must not be scratched, you
can lay a metal shim of known thickness d on it. You
then enter a value that is greater than the desired
preset by the value d.
Operating mode: Press the Manual operation key
Move the tool slowly until it touches (scratches)
the workpiece surface
Select the axis
DATUM SETTING Z=
Zero tool in spindle axis: Set the display to a
known workpiece position (here, 0) or enter the
thickness d of the shim. In the tool axis, offset the
tool radius
Repeat the process for the remaining axes.
If the values for the tool in the tool axis have already been set, set
the display of the tool axis to the length L of the tool or enter the
sum Z=L+d
The TNC automatically saves the datum set with the
axis keys in line 0 of the preset table.
HEIDENHAIN | TNC 620 | ISO Programming User's Manual | 9/2016
Datum setting without a 3-D touch probe 14.6
"Datum setting with a 3-D
14
511