HEIDENHAIN TNC 426 B User Manual page 99

The coordinates for the X, Y, Z positions and the surface-
normal components NX, NY, NZ must be in the same
sequence in the NC block.
3-D compensation with surface-normal vectors is only
effective for coordinates in the main axes X, Y, Z.
If you insert a tool with oversize (positive delta value), the
TNC outputs an error message. You can suppress the
error message with the M function M107 (see section
5.2 "Tool Data, Tool Change").
The TNC will not display an error message if an entered
tool oversize would cause damage to the contour.
Machine parameter 7680 defines whether the CAD
system has calculated the tool length compensation
from the center of sphere P
sphere P .
SP
Using other tools:delta values
If you want to use tools that have different dimensions than the
ones you originally programmed, you can enter the difference
between the tool lengths and radii as delta values in the tool table
or TOOL CALL:
Positive delta value DL, DR, DR2
The tool is larger than the original tool (oversize).
Negative delta value DL, DR, DR2
The tool is smaller than the original tool (undersize).
The TNC corrects the tool position by the delta values and the
surface-normal vector.
Example: Program block with a surface-normal vector
LN X+31.737 Y+21.95
NY+0.0078922 NZ–0.876 339 F1000 M3
LN Straight line with 3-D compensation
X, Y, Z Compensated coordinates of the straight-line end
point
NX, NY, NZ Components of the surface-normal vector
F Feed rate
M Miscellaneous function
The feed rate F and miscellaneous function M can be entered and
changed in the Programming and Editing mode of operation.
The coordinates of the straight-line end point and the components
of the surface-normal vectors are to be defined by the CAD system.
HEIDENHAIN TNC 426 B, TNC 430
www.EngineeringBooksPdf.com
or the south pole of the
T
Z+33.165 NX+0.2637581
P
T
P
SP
R
L
R2
DR2>0
DL>0
83