TNC 426/TNC 425/TNC 415 B/TNC 407
2 - 7
2
Manual Operation and Setup
Fig. 2.5:
Workpiece setting in the tool axis;
right, with protective shim
Z
X
Z
X
d
ELECTRONIC HANDWHEEL
only:
e.g.
0
ENT
Z
e.g.
e.g.
ENT
0
5
or
2.3 Setting the Datum Without a 3D Touch Probe
You fix a datum by setting the TNC position display to the coordinates of a
known point on the workpiece. The fastest, easiest and most accurate
way of setting the datum is by using a 3D touch probe from HEIDENHAIN
(see page 2-14).
To prepare the TNC:
Clamp and align the workpiece.
Insert the zero tool with known radius into the spindle.
Select the MANUAL OPERATION or ELECTRONIC HANDWHEEL
mode.
Ensure that the TNC is showing the actual values (see page 10-8).
Setting the datum in the tool axis
Fragile workpiece?
If the workpiece surface must not be scratched,
you can lay a metal shim of known thickness
d
on it. Then enter a tool axis datum value that is
larger than desired datum by the value
d.
Move the tool until it touches the workpiece surface.
Select the tool axis.
Select datum setting.
Zero tool. Set the display to Z = 0 or enter the thickness
d of the shim.
Preset tool: Set the display to the length
L of the tool,
(here Z = 50 mm or enter the sum Z = L + d
