To Create Envelope
Activate electrode component to access design ribbon before starting feature definition..
Use Surface  Quilt Envelope to create a rectangular quilt enclosing selected surfaces.
  1. Select surfaces or quilts from electrode or workpiece.
  2. Click Surface  Quilt Envelope to open user inteface showing outline and position of quilt to create.
  3. Adjust position and size.
  4. Click OK to create quilt.
Selected references are copied and defined quilt is created with transparency. A new group named Region appears in modeltree. Use quilt for further detailing like expand, trim, merge and solidify.
Example
1.
Select surfaces.
2.
Click Surface  Quilt Envelope.
3.
A preview of outline of selected surfaces (dashed) and later quilt (solid) is displayed.
4.
Adjust size and position.
5.
Click OK to create quilt.
6.
Select group in modeltree and select Redefine Cutout in mini toolbar to reopen user interface.
7.
Edit size/position and confirm changes with OK .