AutoCAD is a widely used software for creating 2D and 3D designs, and it offers a variety of tools for viewing and navigating 3D solid objects. Viewing 3D solid in AutoCAD is essential for effectively designing and modeling complex structures and components. Here are some tips on how to view 3D solid in AutoCAD:

1. Use the ViewCube: The ViewCube is a visual aid that allows you to orient and rotate the model in 3D space. It provides the ability to easily switch between standard and isometric views, as well as rotate the model along its axes. You can click and drag the ViewCube to reposition the model in the drawing area.

2. Utilize the Orbit Tool: The Orbit tool enables you to freely rotate the 3D model in any direction. Simply select the Orbit tool from the navigation bar, then click and drag the mouse to orbit the model. This allows you to view the 3D solid from different angles and perspectives.

3. Use the 3DORBIT Command: The 3DORBIT command offers more control over the 3D model's orientation. You can access this command by typing '3DORBIT' in the command line and pressing Enter. Then, click and drag the mouse to orbit the model in 3D space. This command provides greater flexibility in navigating and exploring the 3D solid.

4. Explore Visual Styles: AutoCAD offers various visual styles that allow you to view the 3D solid in different representations, such as wireframe, hidden, shaded, and realistic. You can access these visual styles from the Visual Styles panel in the 3D modeling workspace. Experimenting with different visual styles can help you better understand the spatial relationships within the 3D solid.

5. Use the Section Plane: The Section Plane tool enables you to cut through the 3D solid and view its internal structure. You can create a section plane by selecting the Section Plane tool from the navigation bar and positioning it within the 3D model. This feature is particularly useful for inspecting the internal components of a complex solid.

By utilizing these tools and techniques, you can effectively view and navigate 3D solid objects in AutoCAD. Whether you're designing mechanical parts, architectural structures, or industrial equipment, understanding how to view 3D solid in AutoCAD is crucial for creating accurate and detailed models.