SolveSpace (solvespace.com) is parametric CAD sofware that is free and easy to start with. You can use it to create 2D, 3D designs and assemblies. It has very good 2D graphics and 3D mesh export capabilites. Pick this one up and you won't be dissappointed.
0:00 Introduction
3:00 User Interface Walk-Through
5:05 Drawing in 2D and Constraints
10:30 Creating 3D Object from a 2D Drawing
11:38 Mirroring 3D Geometry
13:41 Drawing on Existing 3D Geometry
20:48 Cutting Through 3D Object using 2D Geometry
24:50 Creating Another Part
28:14 Creating an Assembly
32:25 Exporting Triangle Mesh
33:14 Exporting 2D Drawing for Lasercutting
