Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 524)

Tool Tip Radius Compensation (TTRC)
Function
Chapter 21
21-40
When scanning ahead, if the control does not find a motion block before
the number of non-motion blocks has been exceeded, it does not generate
the normal TTRC move. Instead the control sets up the compensation
move with an end-point one-tool radius away from and at right angles to,
the programmed end-point. In many cases this may cause unwanted
overcutting of a work piece.
In many cases, this can cause unwanted overcutting of a work piece.
Figure 21.35 and Figure 21.36 are example tool paths of programmed
motion blocks followed by too many non-motion blocks before the next
move was made.
Figure 21.35
Too Many Non-Motion Blocks Following a Linear Move
Too many
non-motion
blocks here
Too many
non-motion
blocks here
Too many
non-motion
blocks here
Too many
non-motion
blocks here
End-point of compensated
move if not too many non-mo-
tion blocks
Compensated
path, G41
Compensated
path, G41
Compensated
path, G42
Compensated
path, G41
Programmed
path
Programmed
path
Programmed
path
Programmed
path
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