M. To add a density line or point

In the Parametric Models dialog Mesh Models list, click on the leaf called Density Lines or Density Points under the mesh model to which you wish to add an opening.
Click Add.
The drawing will change to display just the mesh region. The right hand side of the screen will display a grid with the grid line settings and spacing.

Tip: The various viewing options and zoom options on top of the screen can be used to obtain a convenient view of the panel.
(Optional) Edit the grid positions using the Snap Node/Panel
Either:

Click the start and points of a density line.

or
Click a density point.

The mesh is regenerated to account for the new density line or point
Repeat step 4 as many times as needed.
To stop adding density points or density lines, press the <Esc> key.

Tip: To delete a parametric mesh, opening, density line, or density point, select that entry within the Parametric Models dialog and click Delete.