LibreCAD is one free application Open Source CAD for Windows, Mac and Linux. Support and documentation are free by a large, dedicated community of users, partners and developers.
LibreCAD started as a project to create CAM capabilities in the community version of QCad for use with a Mechmate CNC router.
As QCad CE was developed with the old Qt3 library, it had to be ported to Qt4 before further improvements. This led to CADuntu.
The project was only known as CADuntu for a few months before the community decided that the name it was inappropriate. After some discussion and research on existing names, CADuntu was renamed to LibreCAD.
Porting the rendering engine to Qt4 turned out to be a big project, so LibreCAD initially depends on the Qt3 support library. The port to Qt4 was finally completed on duration of series 2.0.0 development, thanks to lead developer Rallaz.
Meanwhile, for the LibreCAD 2.2.0 series, Qt5 is required.
Download the application at platform you are interested in