Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 656)

Milling Fixed Cycles
Chapter 26
26-24
Figure 26.11
G84: Right-Hand Tapping Cycle
Hole bottom
Spindle rotation direction
reversed at hole bottom
Spindle rotation
in the forward
direction
Z
R
initial point
level
Cutting feed
Rapid feed
R point level
1
2
3
4
5
6
7
In the G84 right-hand tapping cycle, the control moves the axes in the
following manner:
1. The tool rapids to initial point level above the hole location.
2. The threading tool then rapids to the R point level, slows to the
programmed cutting feedrate and begins the tapping operation.
3. During the tapping operation, the control infeeds the threading tool to
the depth and at the feedrate programmed in the tapping cycle.
4. If a value was programmed for the P parameter, the threading tool
will dwell after it reaches the bottom of the hole and after the spindle
has been commanded to reverse.
The spindle reverses to the counterclockwise direction.
5. The threading tool retracts at the cutting feedrate to the R point.
6. If a value was programmed for the P parameter, the threading tool
will dwell after it reaches the R point level. (Dwells may be ignored
if the system installer has chosen to do so in AMP.)
Then the spindle direction is reversed to clockwise.
7. With G98 active, the cutting tool will then accelerate to the rapid
feedrate and retract to the initial point level.