Tool Radius Compensation (D, G40, G41, G42)

D

D<v>

Select tool v. The new tool applies to its own block and all succeeding blocks until a new tool is selected. Tool 0 is special. Its selection deactivates any tool compensation. Tool 0 can be regarded as tool where all tool parameters are set to zero. It is selected by default.

Example:

In the following example tool 1 is defined to have a Y-offset of 10 and tool 2 to have an Y-offset of 20. Block N10 and block N50 use tool 0. Tool 1 applies to block N20 and to block N30. In block N40 tool 2 is active. Figure “ExampleD” shows the resulting programmed path (dotted line) and the resulting tool center point path (solid line).

!toolSet(index:=1, nr:=1, offsetY:=10);
!toolSet(index:=2, nr:=2, offsetY:=20);
N10 G01 X10 Y0 F6000
N20 G01 X20 Y0 D1
N30 G01 X30 Y0
N40 G01 X40 Y0 D2
N50 G01 X50 Y0 D0
M02

Figure “ExampleD”.

G40

Deactivate Tool Radius Compensation (TRC).

G41

Activate tool radius compensation (TRC). After activation the programmed path is shifted left by the radius of the currently selected tool. (See D.)

On activation, a tool with a nonzero index must be selected.

Example:

The following example demonstrates the activation and deactivation of tool radius compensation. The programmed path (dotted line) and the compensated path (solid/ dashed line) are shown in Figure “ExampleG40G41”.

• The first line of the GST program sets the offset parameter to 5 mm. Therefore, the adjacent segments of a gap are extended by 5 mm. The remaining gap is closed by a circular arc.
• The second line defines the approach and depart behavior to use a circular arc with a radius of 5 mm and an angle of 90 degree.
• The third line defines tool 1 to have a radius of 10.
• Block N10 describes a linear movement to [10,0,0].
• The next block N20 selects tool 1 and activates tool radius compensation, where D1 comes into effect before G40 is processed and G40 is active before X20 is processed. Therefore, the end of segment N20 is subject to TRC (tool radius compensation). The linear movement from the end of segment N10 to the end of segment N20 in the programmed path is substituted by an approach-segment (dotted line) from the end of N10 to the end of N20' in the compensated path.
• In the next three lines a linear movement along N30, N40 and N50 is programmed. Since segment N40 would result in a collision, it is eliminated from the compensated path.
• In the next line a circular arc along N60 is programmed. The gap between the end of N50' and the beginning of N60' is closed as described earlier.
• The line along N70 is the last segment that is subject to TRC (tool radius compensation), since its deactivation becomes active before the end of N80. The line along N80 is replaced by the depart-segment N80', similarly to the approach-segment.

!trcOffsetSet(offset:=5);
!trcApproachDepartSet(approachRadius:=5, approachAngle:=90, departRadius:=5, departAngle:=90);
!toolSet(index:=1, tooltype:=tooltypeMill, radius:=10);
N10 G01 X10 F6000
N20 X20 G41 D1
N30 X35
N40 X40
N50 Y20
N60 G02 X50 Y10 U10
N70 G01 X70
N80 X80 Y0 G40
N90 X90
M02

Figure “ExampleG40G41”.

G42

This function is the same as G41, except that the path is shifted to the right. See G41 for details.