cad2shop vs. FreeCAD

FreeCAD is an open-source parametric 3D modeler primarily developed for the design of real objects of any size. Parametric modeling allows users to easily and quickly change their design by going back to the model history and modifying the parameters. FreeCAD is a highly customizable, extendable, multiplatform (Windows, Mac, and Linux) software. It reads and supports many open file formats such as STEP, IGES, STL, SVG, DXF, OBJ, IFC, DAE, and many others, making it seamlessly integrate into the workflow.