NaroCAD is a fully fledged and extensible 3D parametric modeling CAD application. It is based on OpenCascade. A CAD software to help you with your work. The goal of this project is to develop a fully fledged and extensible 3D CAD software based on the concept of parametric modeling of solids, comparable to well known solutions. These functionalities are interrelated through Model Associativity and are exposed through a GUI. The general usability specifications like saving, importing are described in General functionality specifications . The software can be extended through Plugins and programming interface.
Download : http://sourceforge.net/projects/narocad/
Website: http://narocad.com