Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set - Manual (Page 507)

Dresser/Wheel Radius Compensation
Chapter 15
15-19
If the move following the entry move is an arc, the dresser/wheel is
positioned at right angles to a tangent line drawn from the start-point of
that circular move.
Figure 15.16
Dresser/Wheel Path for Entry Move Straight Line-to-Arc
0
≤ θ ≤
90 90
≤ θ ≤
180
180
≤ θ ≤
270 270
≤ θ ≤
360
Start-point
Start-point
Start-point
Start-point
Programmed path
Programmed path
Programmed path Programmed path
G41 G41
G42
G42
G41
θ
r
r
θ
r
r
G41
G42
r
r
θ θ
G42 r
r
12108-I
There is no limit to the number of blocks that can follow the programming
of G41 or G42 before an entry move takes place. The entry move is
always the same regardless of the number of blocks that do not program
motion in the current compensation plane.