3D File Format converter

There are many 3D file formats used for many applications from games to CAD design files, etc.

Some open-source software like Blender, FreeCAD, Meshlab, etc has native support to convert/export to many formats, and there are also some external plugins for these softwares to let them to export even for more formats.

But if you need a command line 3D file converter assimp is a good option:

http://assimp.sourceforge.net

But assimp still missing STEP and Parasolid format support. I think STEP became the defacto format to exchange 3D files between many CAD tools.

Sites com milhares de modelos 3D gratuitos para download

Se você está procurando modelos de algum objeto em 3D então é provável que você encontre neste site:

http://archive3d.net

Outro site que também possui muitos modelos é o grabcad:

http://grabcad.com