Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 630)

Irregular Pocket Milling Cycles
Chapter 25
25-12
Figure 25.6
Irregular Pocket Finishing Cycle Entry Moves
Start wall (defined
in block called out
by P parameter
Will leave H finish
allowance if programmed
in the G89.2 block
TOP
VIEW
End wall (defined
in block called out
by Q parameter)
Start-point
Start/end corner
X
Y
Initial Z level (top of pocket)
SIDE
VIEW
c
d
b
A
C B
D
Z
(incremental)
Z
(absolute)
X
Z
L
D
A/B
C
H
e
If H is programmed in the G89.2 block, an initial finish pass that leaves a
finish allowance is made around the sides of the pocket. This typically
would be done when it is desirable to clean out the corners in an irregular
pocket before actually removing the finish allowance.
If H is not programmed in the G89.2 block, a finish pass is made around
the sides of the pocket that removes all the finish allowance that was left
during a G89.1 roughing cycle.