Use this procedure to add grid lines to a layout volume. You can add grid lines on the X, Y, and Z planes separately.
Note: You can add lines only to volumes inserted with manually spaced lines or evenly spaced lines. Layout volumes with lines placed at a fixed repeated spacing value cannot be changed.
- Select the layout volume.
- Specify the axis to which to add the grid line:
If you want to add… Then… a grid line to the X plane of the volume click 
. 
a grid line to the Y plane of the volume click . 
a grid line to the Z plane of the volume click . 
- Specify the distance of the new grid line from the start of the grid.
- If you have added a line to a layout volume with manually spaced lines, the new line is inserted at the specified position. The position of the other lines remains unchanged. The grid size changes accordingly.
- If you have added a line to a layout volume with evenly spaced lines, the new line is inserted and all lines are recalculated, so that they are evenly distributed again. The grid size remains unchanged.