HEIDENHAIN iTNC 530 (340 49x-04) ISO programming - Manual (Page 290)

290 7 Programming: Miscellaneous Functions
7.
5 Miscellaneous F
unctions f
o
r Rotary Ax
es
After M128 you can program another feed rate, at which the TNC will
carry out the compensation movements in the linear axes. If you
program no feed rate here, or if you program a larger feed rate than is
defined in MP7471, the feed rate from MP7471 will be effective.
Reset M128 before positioning with M91 or M92 and before a
TOOL CALL.
To avoid contour gouging you must use only spherical
cutters with M128.
The tool length must refer to the spherical center of the
tool tip.
If M128 is active, the TNC shows the symbol in the
status display.
M128 and M116 cannot be active at the same time, they
exclude each other. M128 executes compensation
movements that must not change the feed rate of the tool
relative to the workpiece. The compensation movement is
carried out very accurately with a separate feed rate—
which you can define in the M128 block—in parallel and
independently of the machining feed rate. When M116 is
active on the other hand, the TNC must calculate the feed
rate at the cutting edge during movement of a rotary axis
in such a way that the programmed feed rate also results
at the cutting edge of the tool (at the tool center point,
TCP). In doing so, the TNC takes into account the distance
of the TCP from the center of the rotary axis.