Mirroring with axis specification (G351)
G21 to G23 only select mirroring only for the first two main axes. The syntax with G351 described below permits free programming for axis mirroring.
Syntax: | |
G351 <axis_name> [ [+] | - ] 1 { <axis_name> [ [+] | - ] 1 } | non-modal |
G351 | Axis-specific selection of mirroring. The G function G351 is only valid as non-modal. However, mirroring is modal for an axis programmed with this function (modal). | |
<axis_name>.. | The axis coordinate defines whether to select or deselect mirroring in the axis. | |
| Coordinate value -1: | Selects mirroring |
| Coordinate value 1 or +1: | Deselect the mirroring function |
Programing Example
Mirror with axis specification (G351)
G351 X-1 Y1 Z+1 (Select mirroring in the X axis and deselect mirroring)
(in the Y and Z axes)
- The axes mirrored can be programmed at any point in the NC block.
- At least one axis coordinate must be programmed together with G351.
- The G351 function must be programmed alone in the NC block. An exception is block number N.
- Repetitive selection or deselection of axis mirroring is permitted. However, an error message is output if repeated programming takes place in the same NC block.
- If mirroring is selected in synchronous mode for the lead axis (master axis), mirroring is not automatically selected for the tracking axis (slave axis). However, the slave axis is always tracked according to the path motions of the master axis. Therefore, an additional path motion resulting from mirroring the master axis always influences the slave axis.
- Mirroring is deselected for all axes at program start and reset. When axes are changed, mirroring of the changed axis is deselected.
- Mirroring the first or second main axis influences the path direction during circular interpolation and tool radius compensation.
- When mirroring is programmed when tool radius compensation is active, the selected side (G41/G42) is swapped automatically. This is only allowed for linear blocks.
- If a reference point offset G92 is active in an axis mirrored with G351, the coordinates of the reference point offset are also mirrored.
- The coordinates of the circle centre point I, J, K are also mirrored (see Section Plane selection (G17/G18/G19))
- When chamfers and roundings (G301/G302) are inserted, the I word is read as chamfer length or as radius. Therefore there is no need to consider mirroring here.
Programing Example
Mirror with axis specification (G351)
The examples below show how to use the G351 function. Assuming that the axes X, Y and Z are the 1st, 2nd and 3rd main axes.
N10 G351 X-1 (Select mirroring in the X axis (G21))
N20 G351 Y-1 (Select mirroring in the Y axis (G22))
N30 G351 X-1 Y-1 (Select mirroring in the X and Y axis (G23))
N40 G351 X1 Y+1 (Deselect mirroring in the X and Y axes (G20))
N50 X1 G351 Y-1 Z1 (Select mirroring in the Y axis and deselect) (mirroring in the X and Z axis)