Blender - Blender is the open source, cross platform suite of tools for 3D creation.
PDF24 PDF Creator - Create PDF and convert documents to PDF for free with the free PDF24 PDF Creator.
FreeCAD - An open-source parametric 3D modeler
Foxit PhantomPDF - Edit PDF files with our feature-rich PDF Editor. Download Foxit PDF Editor to convert, sign, scan / OCR & more. A speedy PDF Editor alternative to Adobe Acrobat.
meshmixer - meshmixer is an experimental 3D modeling tool for making 3D mashups without too much hassle.
Adobe Acrobat DC - Make your job easier with Adobe Acrobat DC, the trusted PDF creator. Use Acrobat to convert, edit and sign PDF files at your desk or on the go.