Command entry:Select a shape that already has a Sweep modifier using a Custom Section applied. 


 Modify Panel 

 Section Type rollout 

 Click Extract.
            
  
          The Extract feature allows you to recover custom cross-sections that may have been deleted from the scene. As long as you
            have a Sweep object in the scene that uses the deleted shape as a custom cross-section, you can use Extract to restore the
            shape to the scene.
         
         In a large scene that has many objects and shapes, you can also use Extract if you want to quickly duplicate a section used
            by the sweep instead of searching for the original shape you used as the section.
         
          
            Procedures
            
 
            To extract a section from a sweep:
            
            
               - In a viewport, 
 select a swept shape.
                
               - Go to the 
 Modify panel and in the Section Types rollout 
 Custom Section Types group, click the Extract button.
                  3ds Max opens the Extract Shapes dialog.
                  
                
               - Enter a new name for the extracted section.
 
               - Specify the type of cloned shape you want extracted; a copy, an instance or a reference.
 
               - Click OK.
 
            
 
          
          
            Interface
            
  - Name
 
               - 
                  
 
                     This field shows the default name that will be given to the extracted section. By default, it always has the naming convention
                        of Sweep_ShapeName01, Sweep_ShapeName02, etc.
                     
 
                     For example, if your missing section was named Roman-Ogee, the extracted shape will be named Sweep_Roman-Ogee01.
                     
 
                   
                - Copy
 
               - 
                  
 
                     Places a copy of the extracted section at the global origin (0,0,0).
                     
 
                   
                - Instance
 
               - 
                  
 
                     Places an instance of the extracted section at the global origin.
                     
 
                   
                - Reference
 
               - 
                  
 
                     Places a reference of the extracted section at the global origin.