Bodies

In Fusion, you can create 3D bodies within any component in the assembly of your design.

A Body is a single container for a contiguous 3D shape.

Each body is contained within a component, whether it's located in the Default Component or one that you created intentionally. Each component can contain multiple bodies, but you cannot create joints or motion between bodies. Each body in a component represents a separate but fixed 3D region within that component.

multiple bodies in default component example

If you need to create joints and motion between bodies, they need to reside in separate components.

Tip: If you turn on Display Component Colors component colors icon(Shift+F), it becomes easy to tell which bodies reside in each component.

multiple bodies in separate components example

Types of bodies

You can create several types of bodies in Fusion.

Each body type is represented by different underlying math. This means that two bodies of different types cannot interact. You need to convert bodies to the same type before you can perform operations between them.

Solid and Surface bodies

Solid and Surface bodies are the primary body types in Fusion.

You can create solid and surface bodies in the Design workspace. The tools on the Solid and Surface tabs are the most suitable for creating precise, sketch-based, parametric geometry.

This sets you up to use the full assembly, simulation, documentation, and manufacturing toolsets downstream.

Sheet Metal bodies

You can create Sheet Metal bodies in the Design workspace in parametric modeling mode only. The tools on the Sheet Metal tab let you apply sheet metal rules and design flat patterns to be manufactured from a flat piece of metal with a consistent thickness.

T-Spline bodies

You can create T-Spline bodies in the Design workspace, in the Form contextual environment. These bodies let you create and modify more freeform, sculptural shapes.

Mesh bodies

You can import STL, OBJ, or 3MF files as Mesh bodies.

Mesh bodies are generally used as reference geometry for downstream modelling. You can either convert them to solid or surface bodies, or remodel them as T-Spline bodies.

You can also use the tools on the Mesh tab to modify mesh bodies. You can covert other body types to mesh bodies, then use the mesh editing tools to modify them.

Creating and modifying bodies

You can create primitive bodies using the Box, Cylinder, Sphere, Torus, Coil, and Pipe commands.

primitive bodies example

You can also create more complex bodies based on sketches, by using commands like Extrude, Revolve, Sweep, Loft, Hole, Pattern, and Mirror.

complex body example

You can modify bodies with commands like Fillet, Chamfer, Shell, Draft, Combine, and Split Body. You can even use bodies as tools to modify other bodies within the same component.

If you split a single body, it becomes two bodies, because the original 3D shape is no longer contiguous.

Creating components from bodies

If you've already created bodies in the Default Component, you can move the bodies to separate components later using the Create Components from Bodies command. However, the history of features and operations you used to create the original bodies remain in the Default Component and are still associated with full assembly timeline, instead of moving to the components' specific timelines.

This makes the timeline difficult to understand and interact with as you evolve your design, especially if you're collaborating with others.

This is why it's considered best practice to create a new component first, name it, activate it, and then start designing.

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