FreeCAD is an Open-Source Computer Assisted Drawing (CAD) software but more focused on mechanical designs and geometric constraints.
The main feature is it parametric geometry engine and it's modifiers pile, overpowered by the OpenCascade library. For thoses who already know SolidWorks , the GUI is quite designed the same way.It is fully compatible with KiCAD 3D parts, that's why it could be very useful to design cases
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