Create a Void Family with an Elliptic Profile

Learn how to model a void family with an elliptic profile.

1. Create a new family using the Metric Generic Model face based.rft template.
2. Select the 3D Front view.
3. Click Create tab Datum panel (Reference Plane).
4. Place a new horizontal reference plane in the middle of the slab extrusion:
   
   
   
5. Select the new reference plane.
6. In the Properties palette:
   • Specify the Is Reference parameter as Select Center (Elevation).
   • Select Defines Origin.
7. Click Create tab Forms panel Void Forms (Void Extrusion).
8. Create a new ellipse under the new reference level using the Ellipse tool on the Draw panel:
   
   
   
9. Select the ellipse.
10. In the Properties palette, select Center Mark Visible.
11. Create two dimension lines from the center mark of the ellipse to the origin defined by the reference planes:
    
    
    
12. Select the ellipse, set both dimension values to 0 to move the ellipse to the origin and lock to create a constraint mark of the ellipse to the origin defined by the reference planes:
    
    
    
13. Create dimension lines for both radiuses of the ellipse:
    
    
    
14. (Optional) Define parameters for the dimension lines for the radiuses in the Parameter Properties. For example, Radius_Vert and Radius_Horiz.

    Type parameters are only necessary if family types for different sizes of the hole are created.

15. Click Modify | Create Extrusion tab Mode panel (Finish Edit Mode).
16. Create a dimension line from the previously created reference plane to the top edge.
    
    
    
17. Add the Position from top instance parameter as a shared parameter to this dimension line.
    
    
    
18. Open the Floor Plan Ref. Level view and then select the void extrusion object. In the properties, set the Extrusion Start to 0.0. Then, click the button next to Extrusion End and bind this to the Length of Instance shared parameter as an instance parameter. Verify that the extrusion starts at the origin reference plane:
    
    
    
19. Create tab Properties panel (Family Category and Parameters). Select:
    • Cut with Voids When Loaded
    • Shared
20. Click OK.
21. Click Create tab Properties panel (Family Types).

    In this example two types are created - 40x80 and 60x90:

    • Click (New Type), type the name (40x80), and modify the parameters.
    • Click (New Type), type the name (60x90), and modify the parameters.
22. Click OK and save the file.