FREE 3D PDF from Inventor STL using U3D-2-PDF

The two step process is:

1. Export STL file from Inventor
2. Use U3D-2-PDF to turn the STL into a 3D PDF (a one click process).

You will need to setup your environment first. Here is what you need: 

 

Get U3D-2-PDF at:
http://sourceforge.net/projects/u3d2pdf/?source=recommended

It requires MeshLab and MiKTeX (see here). 

You can get them from:

3) Meshlab software:
http://sourceforge.net/projects/meshlab/?source=recommended
and
4) MiKTeX download at:
http://miktex.org/download

(yes to automatic package installs)

Once you have installed all items, then:
Extract and Run U3D-2-PDF.exe. You will need to specify some paths like:
"C:\Program Files (x86)\MiKTeX 2.9\miktex\bin\pdflatex.exe"
"C:\Program Files\VCG\MeshLab\meshlabserver.exe"

Select the STL file, then an output PDF filename and click Start. Once finished, click Open PDF.