Conversion from Nastran to 3MF is not supported yet :(

MSC Nastran is a multidisciplinary structural analysis application used by engineers to perform static, dynamic, and thermal analysis across the linear and nonlinear domains, complemented with automated structural optimization and award winning embedded fatigue analysis technologies, all enabled by high performance computing.

Engineers use MSC Nastran to ensure structural systems have the necessary strength, stiffness, and life to preclude failure (excess stresses, resonance, buckling, or detrimental deformations) that may compromise structural function and safety. MSC Nastran is also used to improve the economy and passenger comfort of structural designs

The 3D Manufacturing Format (3MF) is a 3D printing format that allows design applications to send full-fidelity 3D models to a mix of other applications, platforms, services and printers. The 3MF specification allows companies to focus on innovation, rather than on basic interoperability issues, and it is engineered to avoid the problems associated with other 3D file formats.