You can insert a new, empty subassembly at any level of the assembly
hierarchy. Then you can add components to it in a number of ways.
Before you begin:
Specify the default behavior for saving new in-context components.
You can save them as separate external part files or as virtual components within
the assembly file. See Saving New In-Context
Components.
To insert a new subassembly:
To save a virtual component to its own external file, right-click
the component and select Save Assembly(in External
File). Alternatively, when you save the assembly, you can select to
save the subassembly either inside the assembly or to an external file.