MEDUSA4 Personal, the free version of the company’s 2D/3D CAD suite, is suitable for hobby engineers who build models from scratch or professionals who design model engineering kits.

DraftSight 2D CAD software, which lets users create, view, and edit DWG and DXF files, is free -- and it comes with its own online social-networking communities.

Computer-aided design software costs vary dramatically across the market. Professional CAD software ranges from $119 annually ...