Convert NWD to NWF

As far as we know, the only reliable way to create a .nwf file from a .nwd file would be to use Autodesk NavisWorks software that uses both these files types. Considering a .nwd file is a complete file and the .nwf is somewhat limited, it is likely that nwd to nwf conversion is indeed doable. It might be possible that some 3rd party viewers can accomplish this as well, however it is usually more safe to use the original tool.