Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 488)

Tool Tip Radius Compensation (TTRC)
Function
Chapter 21
21-4
This table highlights the differences between the two types:
Type of Move Type A Type B
Entry Move Into
TTRC
-- The tool takes the shortest possible
path to its offset position.
-- The tool stays at least one radius away
from the start-point of the next block at
all times.
-- Extra motion blocks can be generated
to attempt to prevent gouging of the
part as may occur in Type A.
Tool
Path
-- Same as Type B. -- Same as Type A.
Exit Move From
TTRC
-- The tool takes the shortest path to the
end-point of the exit move for both
inside and outside corners.
-- The tool takes the shortest path to the
end-point of exit move for inside
corners only.
-- For outside corners, the tool stays at
least one radius away from the
end-point.
Your system installer determines whether to use type A or type B by a
control in AMP.
These G-codes are used for TTRC:
G-code: TTRC, :
G41 left
G42 right
G40 cancel
Left or right is defined as offsetting the tool to the left or right of the
programmed cutting path when facing the direction of cutter motion.
Important: If you set a negative value in the offset tables as the tool
radius, this reverses compensation direction (tool left or right) for the G41
and G42 codes. G41 and G42 are also reversed during the mirroring
operation. See chapter 14.
All of these G-codes are modal and belong to the same modal group.
21.1
Programming TTRC