The assembly feature command allows users to create holes in several parts at the same time from one individual part. This Assembly feature will drill into any part that it is touching and remove material. What makes this different from a part feature is that these Assembly features can be used to cut through any part it contacts or just the ones you want.  If you move a part that is being affected by an assembly feature, you will notice that the cut will no longer show or move with that part as it is not really a feature of the part yet. If this isn't the intent you want and you want it to be a real feature, you can use the option to create a part feature to have the assembly feature create a new feature under your affected parts. This tool is excellent when you have to drill holes that travel through several parts and assemblies because, by default, IronCAD features do not apply to multiple parts at once.

The Assembly Feature command has a couple of options upon creation that allow you to determine the scope of the assembly feature. 

• By default, the assembly feature will only apply to the part that it is dropped on, meaning that it will only affect the one part, much like a feature.
• The "Apply to all assemblies/parts under the affected level"  command will allow the assembly feature to cut through all geometry inside the scene. This option does not affect any new parts that are added into the scene.
• Lastly, the "Empty" option does not cut through any parts in the scene, and all parts must be added inside the Assembly features right-click menu with the "Edit assembly feature scope" command. This command allows you to select a part in the scene and remove or add it to the list of parts that the Assembly feature will cut through.

IronCAD mechanical expands on the Assembly feature command by allowing users to create solid shapes that will cut through parts with which they interact. This command will enable you to do things like place piping through walls or cut elements intersecting with other parts with just a simple drag and drop. You can also create offsets for the drilled parts that automatically cut a clearance for your parts. This command is enabled by renaming the features you want to cut through other parts "drill", and IronCAD will automatically cut it for you when you drop the tool out into the scene. You can remove the drill cuts by using the Remove DrillHoles at any time for easier editing.