Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 529)

Tool Tip Radius Compensation (TTRC)
Function
Chapter 21
21-45
Figure 21.41 describes the tool path when the programmed moves are
circular-to-circular.
Figure 21.41
Circular to Circular Change in Cutter Radius During Compensation
No control-generated
motion blocks
With control-generated
motion blocks
Programmed
path
Compensated
path
r
1
r
2
r
2
r
2
r
1
r
1
Programmed
path
Compensated
path
Generated blocks
Change in Cutter Radius During Jog Retract.
This section concerns a change in the cutter radius during a jog retract
operation. The jog retract feature is often used when a tool becomes very
worn or is broken. It can be necessary to replace the tool with a tool of a
slightly different diameter. TTRC is able to adjust to the new tool
diameter.
Typically when the jog retract operation is performed, the tool is jogged
away from the workpiece and then replaced. After it is replaced, you need
to activate a different tool diameter offset value. This is done in either of
two methods:
The new offset number is activated by programming a new D-word in
an MDI block.
The new offset number is activated by using the {ACTIVE OFFSET}
softkey found on the offset table screen. This feature is described in
chapter 3.