I've seen questions in the past regarding the creation of binary STL files.
Inventor only creates ASCII STL files. (Don't ask me why because I don't
know.) For those of you that need binary files I've created a small
converter utility. The executable is attached along with the source code,
if you're interested in how it was written. It was written using VB Express
2005. This is a free version of Visual Basic.
To use the converter, just run ConvertSTL.exe. A dialog will be displayed
where you can pick the existing ASCII STL file and specify the filename of
the binary file. It's also possible to use this in a more automated way
since is supports command line arguments. The first argument is the ASCII
STL filename and the second argument is the binary STL filename.
--
Brian Ekins
Autodesk Inventor API