Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set User Manual
Page 667
Milling Fixed Cycles
Chapter 26
26-35
Important: The programmer or operator must start spindle rotation.
Figure 26.15
G88: Boring Cycle, Spindle Stop/Manually Out
Cutting feed
Rapid feed
Manual operation
Spindle rotation in
the forward direction
Cycle start
Spindle stops at hole bottom after dwell
Hole bottom
R point level
Initial
point
level
R
Z
1
2
3
4
5
6
7
In the G88 boring cycle, the control moves the axis in the following
manner:
1.
The tool rapids to the initial point level above the hole location.
2.
The boring tool then rapids to the R point level, slows to the
programmed cutting feedrate and begins the boring operation.
3.
The boring tool bores at the programmed feedrate until it reaches the
depth specified with the Z--word.
4.
If the user has entered a value for the P parameter, the boring tool will
dwell after it reaches the bottom of the hole.
5.
After the tool reaches the Z depth, the spindle stops revolving. At
this point, the operator must perform a manual retraction of the
drilling axis as described in chapter 4. (Press <CYCLE START> to
return the control to automatic mode.)
6.
The boring tool is then retracted at a rapid feedrate to initial point
level, as determined by G98.