If you're in need of CAD models for your projects, whether it's for 3D printing, architecture, or manufacturing, there are several websites where you can find high-quality designs for free. Here are 10 websites that offer an extensive collection of CAD models for you to download and use in your projects.

1. GrabCAD: With over 4 million free CAD models, GrabCAD is a leading platform for engineers, designers, and manufacturers to access a wide range of 3D designs.

2. Thingiverse: Owned by MakerBot, Thingiverse offers a vast library of user-generated 3D designs, including CAD models that are free to download and use.

3. MyMiniFactory: This platform is known for its curated collection of high-quality 3D printable models, including a selection of free CAD designs.

4. Free3D: As the name suggests, Free3D provides a large database of free 3D models, including CAD files for various applications such as gaming, architecture, and product design.

5. Cults: Cults is a marketplace for 3D designs, but it also offers a section dedicated to free CAD models contributed by the community.

6. TraceParts: With a focus on industrial CAD models, TraceParts provides access to a wide range of free 3D designs for manufacturing and engineering applications.

7. CAD Blocks Free: If you're specifically looking for architectural CAD models, CAD Blocks Free offers a collection of free 2D and 3D designs for building and interior design projects.

8. BIMobject: Specializing in building information modeling (BIM) content, BIMobject provides free access to a vast library of CAD models for architecture, construction, and interior design.

9. 3D Warehouse: Owned by SketchUp, 3D Warehouse is a platform where users can share and download free 3D models, including a variety of CAD designs for architecture and interior design.

10. Open3DModel: This website offers a diverse range of free 3D models, including CAD files, for use in various industries such as gaming, animation, and virtual reality.

Whether you're a hobbyist, professional designer, or engineer, these websites offer a wealth of free CAD models to support your projects. From architectural elements to mechanical components, you can find a wide variety of 3D designs to enhance your work without having to spend a dime.