Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 575)

Using Pocket Milling Cycles
Chapter 22
22-3
Where : Is :
E Plunge feedrate. This parameter determines the feedrate of any Z axis moves. If
not programmed, the roughing feedrate (F) will be used.
F Roughing feedrate. This parameter determines the feedrate of any XY axis
moves. If not programmed, the existing (modal) feedrate will be used.
Important: The rectangular pocket does not have to be parallel to the axes
of the selected plane. It may be rotated by rotating the work coordinate system
(G68). Refer to chapter 13 for additional information on rotating the work
coordinate system.
Figure 22.1
Rectangular Pocket Roughing Using G88.1
J
I
R
45
•
Plunge Position
D/2
D
D
H+TR
(X, Y)
Y
X
Important: The tool should be positioned near the center of the pocket
prior to the G88.1 block. The Z coordinate of this position determines the
initial Z level or top of the pocket. This is the pre-cycle position of the
tool. The pre-cycle position must be at some depth other than the cycles
programmed final depth or an error is generated.
From the pre-cycle position, the control simultaneously raises the tool by
the clearance amount (AMP selectable, refer to the literature provided by
your system installer) while moving it to the center of the rectangular
pocket specified by the X and Y parameters. This simultaneous move
takes place at the rapid feedrate. The center of the rectangular pocket is
the plunge position, the position where the plunge to the programmed
depth takes place.