Extruding Faces and Edges

This task shows you how to extrude faces and edges.
A CATPart document must be open.
  1. Click Extrusion .

    You can also access this command by pressing ALT+SHIFT+X.
  2. Select a surface.

    A Tools Palette is displayed.
    The following icons let you:

Extruding Faces

Open the Extruding1.CATPart document.
  1. Click Face Extrusion .

  2. Select a face.

  3. Click to add a face.

    An extrusion made of five faces is created. The extrusion direction is normal to the selected face.

Multi-Selecting Faces

  1. Click Face Extrusion .

  2. Press Ctrl to select several faces.

  3. Click to add as many faces as you wish.

     
 
As an alternative, you can also use the Shift key and draw a trap to extrude several faces.
 

Creating a Hole Inside a Closed Surface

Open the Extruding7.CATPart document.
 
  1. Click Face Extrusion .

  2. Press Ctrl and select a face on each side of the surface. Faces must be face to face.

Filling Faces

Open the Extruding10.CATPart document.
  1. Click Face Extrusion .

  2. Press Ctrl to select the four connected faces to fill the hole.

     

 
As an alternative, you can also press Shift and draw a trap to fill the hole.
 

Combining an Extrusion

Open the Extruding5.CATPart document.
  1. Click Face Extrusion .

  2. Press Ctrl to select the two connected faces.

     

Joining Two Unconnected Face-to-Face Faces

Open the Extruding6.CATPart document.
  1. Click Face Extrusion .

  2. Press Ctrl and select the two faces to connect. Faces must be face to face.

     
 
As an alternative, you can also use the Shift key and draw a trap to join the faces.

Extruding Edges

Open the Extruding4.CATPart document.
  1. Click Edge Extrusion .

  2. Select an edge.

    You can only select the free edge of an open surface.
  3. Click to add a face.

    A single face on a plane is created. It is defined by the mean plane of the face connected to the edge.

Multi-Selecting Edges

  1. Click Edge Extrusion .

  2. Press Ctrl to select several faces.

  3. Click to add as many faces as you need.

 
As an alternative, you can also use the Shift key and draw a trap to extrude several faces.
 

Extruding Using the Fill/Inactive Fill Modes

  1. Click Edge Extrusion .

    New icons are available in the Tools Palette.
    They let you:
    • select the Fill mode
 

Fill Mode

  1. Click Fill .

  2. Select any border to fill the hole.

    2 edges:
    3 edges:
    4 edges:
 
You can press Shift and draw a trap to fill a hole.

Extrusion Mode

 
  1. Click Extrusion .

  2. Press Ctrl to select the edges.

    Along an edge:
    With a Corner:
    All edges:
 
The icons and  are used when the extrusion is ambiguous. If there is no ambiguity, only one of both icons is available.
The examples below show this ambiguity.
Open the Extruding9.CATPart document.

Fill mode

Extrusion mode

 
  1. Click Edge Extrusion .

  2. Click Fill .

  3. Press Shift and draw a trap to create the extrusion.

    In our example, we drew two traps:
    Here is the result:
  1. Click Edge Extrusion .

  2. Click Extrusion  .

  3. Use the Shift key and draw a trap to create the extrusion.

    In our example, we drew two traps:
    Here is the result:
 

Propagating Edges

This command lets you propagate the selection to all the free edges.
Open the Extruding9.CATPart document.
  1. Click Edge Extrusion .

  2. Click Propagation .

  3. Select an edge, as shown below:

    All connected edges are selected to create the extrusion.
     
    With propagation of edges   Without propagation of edges
 

Filling Multiple Faces using Propagation

This command lets you propagate the selection to all the free edges to compute a fill.
Open the Extruding11.CATPart document.
  1. Click Edge Extrusion .

  2. Click Propagation .

  3. Select an edge, as shown below:

    All connected edges are selected to create the extrusion.
    You can see that the surface is filled.

  • The number of edges defined for the fill must be lower than 30. If there are more than 30 edges fill a few faces individually and multi-select edges to compute the fill at one time.

  • The number of edges defining the boundary should be in pair i.e. even numbers.

    Add or remove a edge.
    For instance here we have added a edge to make the edges even numbered so that fill can be computed.

    In this case add or remove an edge to make a paired number of even edges.

  • If the edges have an intersection, the fill will not be computed.

    In this case remove the intersecting face.

  • If the selected edges lie on an external boundary, the fill will not be computed.

    In this case fill the external face.

  • The number of edges passing through a point must be 3 or 5. In case of any other number, the fill will not be computed.

  • If the mesh has a symmetry axis or plane before the fill, the mesh after the fill may lose its symmetry characteristic.

Applying the Extrusion

This option lets you validate the previewed extrusion selection and apply the modification.
  1. Click Apply  .

     
    Add Face Mode   Add Edge Mode

     

    • During the modification the selection of elements is previewed on the surface.

    • The modification command is executed, only after the selection is validated by using Apply.

    • Apply is automatic applied before quitting the modification command.

    • When the modification is not possible, the apply button is not active (grayed out).

    • You can undo or redo the changes only after the completion of command after the Apply. Intermediate selection states cannot be managed by undo/redo.