Best 3D Viewers

FreeCAD is an open-source parametric 3D modeler made primarily to design real-life objects of any size. Parametric modeling allows you to easily modify your design by going back into your model history and changing its parameters. FreeCAD allows you to sketch geometry constrained 2D shapes and use them as a base to build other objects. It contains many components to adjust dimensions or extract design details from 3D models to create high quality production ready drawings. FreeCAD is a multiplatfom (Windows, Mac and Linux), highly customizable and extensible software. It reads and writes to many open file formats such as STEP, IGES, STL, SVG, DXF, OBJ, IFC, DAE and many others, making it possible to seamlessly integrate it into your workflow. FreeCAD is designed to fit a wide range of uses including product design, mechanical engineering and architecture. Whether you are a hobbyist, a programmer, an experienced CAD user, a student or a teacher, you will feel right at home with FreeCAD.

Carlson iCAD is an affordable CAD program that works with both .dwg and .dgn files and is designed to fit into your production workflow. Carlson iCAD allows drafters to finish drawings and engineers to review drawings. Functions include move, copy, erase, offset, trim. Smooth, reduce, reverse and edit polylines. Create polylines from lines and arcs. Carlson iCAD has a 3D viewer window that provides 3D display of drawing entities with lighting controls. Set plan rotation for drawing display. Show tooltip of properties as move cursor over entities. The customized user interface helps to control ribbons, menus and workspaces. Commands to label areas defined by linework boundaries.