It appears Autodesk Inventor supports import of STL files, so the most convenient (and likely only) direct way would be to use this program to make this stl to idw conversion. There is really no alternative here, as only Inventor can produce .idw files in reliable quality.
Convert Stereolithography CAD file to AutoDesk Inventor drawing.
We have found one software suitable in our database for this conversion.
Microsoft Windows software - convert stl to idw on Windows
Autodesk Inventor is modeling application used to create 3D digital prototypes.
Convert from stl file format
|Yes, Autodesk Inventor supports idw file conversion as a target file type.||Yes||Yes||idw editor||Yes||No||No||No|
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.