Extract Edges Single Extract Edges SingleThe Extract Edges Single function allows you select one or more individual solid faces, surfaces, or surface edges to extract and create wireframe curves. (Single doesn't refer to a single edge, but rather single selection instead of whole solid selection.)
TIP: It is helpful to create a new layer and set it as the Active layer, before opening the function, to create the extracted curves on the separate layer. Otherwise, you must hide, move, or delete the original geometry to see the curves.
To open Extract Edges Single, do one of the following:
In the Utilities menu, point to Extract Edges and click Single.
On the Utilities toolbar,
click the icon.
Right-click anywhere in the graphics area, point to Utilities, Extract Edges, and click Single.
The parameters display in the 
Data Entry tab
of the Data-CAM Tree Manager.
Select the check box to project the extracted edges to a specified Z-axis
coordinate of the Active UCS.
Clear the check box to extract the edges without projecting them. The
extracted edges retain their exact position on the geometry.
Z - is the Z-axis value to which the edges are extracted when using Project to Z Plane.
You may want to create a new Layer and set it as the Active layer before extracting edges. This makes it easier to hide and show layers so you can see the result.
1 Open the function and set the Data Entry parameters if needed.
2 Click to select one or more solid faces, edges, or surfaces from which you want to extract the edges.
3 To confirm the selection, press the Spacebar. (You can also click OK to confirm the selections.)
The edges are extracted and the wireframe is created in the graphics area.
You may need to move, hide, or delete the original geometry to see the extracted edges.
4 To close the function, click Cancel.