Center constraint in Assembly

You can center parts by referencing one or two objects in the parts. The “Center” in the “Constraint” tab in the “Assembly Constraints” command dialog is used to center parts. 

To center parts in assembly;

1. Start the “Assembly constraints” command.
2. Set the constraint type as “Center”.
3. Look at the “Subtype” in the “Geometry to Constraint” tab. The selection in this tab is important.
   1. 1 to 2: Select one planar object from the first part. Then select two planar objects from the second part to define center in the middle of the selected faces.
   2. 2 to 1: Select two planar objects from the first part then select one planar object from the second part.
   3. 2 to 2: Select two planar objects in the first part. Select two planar faces from the second part. Both parts will be constrained on the center of the selected faces.
4. Click the “Reverse” icon in the command dialog to change the direction of constrained parts if you need it.
5. Finish command.

Note: Also, you can center the axis or edges of the objects.