Well, in the first situation, you're simply switching from one application to another.
While in the second situation, you're creating a totally new file, which just happens to start in the Drafting application, but where the heretofore Work Part is now the 'Master Model', that is the original part file is NOW a first level Component in an Assembly in the new Drawing file.
While it's possible to create a Part Model and have the Drawing data be part of that SAME part model, that is, everything is in the a SINGLE part file, that's NOT the way NX was designed to work at its best. The second situation above is the preferred approach, and long term, it will reap the most benefits in terms of flexibility and overall system performance, particularly if you're designing and manufacturing complex products with multiple parts and configurations and options. Also if you're doing your manufacturing and have to create machine tool paths, fixtures, castings, forgings, in-process models, etc. Also, if you're going to be doing any kind of analysis, like FEA or Heat Transfer or Fluid Dynamics, working in the Master Model mode is really the only way to go and still expect to get reasonable size models files with consistent and acceptable performance.
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
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UG/NX Museum:
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