Your best choice for exporting / saving CAD data to NC1 format from Xsteel would be to use Autodesk AutoCAD or similar software that supports it.
Convert 3D ACIS model file to Xsteel CAD drawing.
We have found 2 software records in our database eligible for .sat to .nc1 file format conversion.
Microsoft Windows software - convert sat to nc1 on Windows
Leading 2D and 3D CAD development software from Autodesk
Convert from sat file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned sat to nc1. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert sat to nc1 on OS X
Mac version of popular Autodesk AutoCAD software