Assemblies
Assemblies are also very different in the 3D modelling
environment. Rather than re-drawing or copying the lines
representing component parts into an assembly drawing, the assembly
is constructed by adding references to component parts and
positioning them together. The assembly itself does not
contain any physical data, instead it has a link to component parts
and their orientation in space. While this means that
assemblies are automatically updated when their component parts are
changed, it does require skilled management of the CAD files to
avoid losing the links between the assembly and its component
parts.