Inquiring the 3D model - Autodesk AutoCAD 2013 Practical 3D Drafting and Design - page 248

Interferences
When dealing with 3D objects, we often need to verify whether there are interferen-
ces.
Detecting interferences and creating solids with a
common volume
The next command allows us to detect interferences between objects and to create
new objects from common elements.
The INTERFERE command
The INTERFERE command (alias INF ) allows us to detect interferences between two
sets of solids or surfaces. If interferences are detected, the command allows the cre-
ation of solids, surfaces, or linear objects corresponding to the intersection, but the
original objects are not affected. This command can be found in the Solid Editing
panel on the Home tab in the ribbon, or on the menu bar by going to Modify | 3D
Operations .
The command starts by prompting for the selection of the first set of objects, then a
second set, and does a comparison between them. If we want to verify all objects, we
just create one selection set. On using the command, it prompts for the first set. The
Enter key is used to finish selecting:
Command: INTERFERE
Select first set of objects or [Nested selection/
Settings]: Selection
It prompts for the second selection set or the Enter key that verifies all interferences
between the objects in the first set:
Select second set of objects or [Nested
selection/checK first set] <checK>: Selection