Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 542)

Cutter Diameter Compensation
(G40, G41, G42)
Chapter 21
21-24
Figure 21.20
Entry Move Followed By Too Many Non-Motion Blocks
Programmed
path
G41
r
r
Too many non motion
blocks here
Cutter compensation
re-initialized here
r
r
r
The cutter compensation feature is cancelled by programming G40. The
path that is taken when the tool leaves cutter compensation is referred to as
the exit move. The path that the tool follows during an exit move is
dependant on:
The direction of compensation (G41 or G42).
The angle between the last motion made in cutter compensation (in the
current compensation plane) and the motion of the of the exit move.
Designating a tool offset number D00 in a program does not cancel cutter
compensation and does not generate an exit move. Cutter compensation
simply continues on as if a tool radius had been changed to a radius of zero
(see section 21.6.4 on changing cutter radius). The exit move, if D00 is the
active tool radius, is then equal to the programmed tool path.
Important: An exit move cannot be a circular move (G02 or G03). Any
exit move must be programmed on a linear path. Any attempt to generate
an exit move using a circular path generates a block format error.
21.4.2
Cutter Compensation
Type B Exit Moves