The Initial Instance The Initial Instance  

Copy Instance Copy #1 Click to remove this copy instance
  Number of Copies Number of Copies  
  Interpolate  Interpolate
Connect Centers  Connect centers
Supress Copying  Supress copying
 
       

Click to add one more copy instance

  Surface Generate Surface    
 
At least two copies needed, so that it will be possible to generate surface.
 
       

Compact View