CadQuery

Parametric CAD through Python code — if you think in scripts rather than GUI, this is the path to fully repeatable, version-controlled mechanical design.

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Browser-based parametric CAD that punches above its weight. Free for hobbyists, version-controlled by default, and far more accessible than SolidWorks for getting started.

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The professional CAD/CAM tool that is actually free for hobbyists. Parametric modeling, integrated CAM, and simulation in one package — the right tool when FreeCAD falls short.

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McMaster-Carr

Every hardware engineer's open secret — the catalog has STEP models for most parts, so you can drop a real McMaster bolt into your assembly and order it the same day.

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