32
R
R
: Programmed path
: Path traveled by center of tool
: Tool
R
: Tool radius
G41
G42
Programmed path
Path traveled by
center of tool
Amount of offset
Start position
Starting Cutter Compensation
Cutter compensation is started with G41 or G42. G41 performs offset to the left-hand side relative to the direction of forward move-
ment. Similarly, G42 performs offset to the right-hand side relative to the direction of forward movement. The direction of offset
cannot be changed while cutter compensation is in progress.
G41 or G42 is specified immediately after positioning (G00) or linear interpolation (G01). Cutter compensation cannot be started with
circular interpolation (G02 or G03). Also, compensation on the PNC-3200 is performed only for the XY plane, and so G17 (setting of
the XY plane) is specified immediately after G00 or G01.
As shown in the figure below (on the left-hand side), the tool is shifted to the left or the right by the amount of offset as it moves
forward from the starting point. Operation takes place when a command for moving to a block is specified when cutter compensation
finishes.
Now let's take a look at tool movement when cutter compensation is started in actual use.
As the following figures show, the shift from the start of offset to the next operation can be classified as travel on the inner side of the
program path, travel on the outer side as an obtuse angle, and travel on the outer side as an acute angle. Outer-side travel includes “Type
A” and “Type B” paths. The settings for Type A or Type B are made using the PNC-3200's display. (Refer to the “User's Manual.”)
Definitions of “Inner Side” and “Outer Side”
Workpieace
< Inner side >
< Outer side >
180
°
or more
0°—180°
Programmed
path
Programmed
path
Path traveled by
center of tool
Path traveled by
center of tool
Workpieace
Programmed
path
Path traveled by center of tool
Amount
of offset
Start position
Inner Side
From a line to a line
From a line to an arc
Start position
Amount
of offset
Path traveled
by center of tool
a
Programmed path
a
(180° a)
<
=