Siemens SINUMERIK 840Di Function Manual page 1756

Detailed Description
2.4 Tool: Tool radius compensation 2D (TRC)
Example
G42 D1 T1
...
G1 X110 Y0
N10 X0
N20 Y10
N30 G40 X50 Y50
Fig. 2-38
The last block with active tool radius compensation (N20) is so short that an intersection no
longer exists between the offset curve and the preceding block (or a previous block) for the
current tool radius. An intersection between the offset curves of the following and preceding
blocks is therefore sought, i.e., between N10 and N30 in this example. The curve used for
the retraction block is not a real offset curve, but a straight line from the offset point at the
end of block N20 to the programmed end point of N30. The intersection is approached if one
is found. The colored area in the figure is not machined, although the tool used would be
capable of this.
G460
With G460, the approach/retraction strategy is the same as before.
2-76
Retraction behavior with G460
; Tool radius 20 mm
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Tool Compensation (W1)