3D printers are increasing in quality and becoming more affordable.  For their relatively low cost, they bring robust rapid prototyping and unique manufacturing capabilities to firms and enthusiasts.  As a result of renewed interest in the technology, 3D printing enthusiasts have started collaborating and sharing their designs online.

If you want to share a design, it is typically a good idea to convert your file to a neutral file format that can be used by anyone.  Luckily, NX CAD and Solid Edge are capable of saving designs with the Initial Graphics Exchange Specification (.igs) format.  The .igs format is CAD neutral and is supported by most 3D slicer programs, which are responsible for communicating designs to the 3D printer.  To save a part as an .igs file, simply click File->Save As and make sure you select the .igs file extension from the drop down menu.
If you have any questions please feel free to ask!