If you’re just starting out with Autodesk Fusion, you’ve probably heard the terms “bodies” and “components” thrown around quite a bit. But what are components in Fusion? What are bodies in Fusion? Why do we need them?

Components and bodies are the foundation of all 3D models in Fusion, so it’s important to understand how to use each and the relationship between them. On that note, let’s get to the fun part. Here are five things you should know about bodies and components in Fusion.

1. Components have their own origin planes, but bodies don’t

A component is a position and motion-independent part of an assembly within the Fusion single design environment. For example, an entire design is the whole assembly design, and each part of the design is a component of the overall assembly. Components have their own origin planes, meaning they can have motion relationships with one another. Components are not dependent on the assembly design’s origin, but they can refer to it.

Bodies, on the other hand, are dependent on the top-level assembly’s origin planes and can not have motion relationships unless converted into a component.

2. A component can contain bodies and other components

Every holistic assembly design contains components. Some components are single-bodied bolts while other components contain other components, making them sub-assemblies. Phew! It sounds overwhelming, but we promise this system is in place for a good reason.

Since Fusion is a single environment for design and assembly, components and bodies help us give our designs organizational structure. You can easily see what is a single part (body or component), sub-assembly (component), or assembly (design). Additionally, you can rename any component without worrying about feature dependencies or where they’re saved.

3. Which comes first — bodies or components?

When creating 3D geometry in Fusion, you always have the choice to start by making a body or a component. If you already know that your design will become an assembly, you should begin by making a component.

When you create a new component, think of it as an empty container that you can fill up with Lego bricks until the container eventually takes your desired shape. The advantage of this workflow is that you can begin to give your features structure right from the beginning.

If you’re not sure about where your design is going yet, you can start by creating new bodies. You can always convert them to components when you’re ready.

4. Active a component to work within it

In scenarios where you have multiple components in a single assembly, be sure to activate the component that you want to work on. This best practice enables you to associate all the features you used to build that component to itself instead of the whole assembly. If you don’t activate the component, all the features will associate with the top-level design by default.

5. Turn Component Color Cycling on

If you’re feeling overwhelmed by a large assembly or simply want an easy way to keep track of all your parts, look no further than Component Color Cycling. Component Color Cycling is a nice and easy way to tell which features in the timeline belong to which component. When you turn this feature on and activate the component you want to work on, the timeline’s features following its creation will display in the same color as the component item shown in your browser to indicate that they are associated.

We hope this post helped you better understand bodies and components in Autodesk Fusion — how and when to use them and why they behave the way they do. Looking for an even more detailed breakdown? Check out the video below:

Download Fusion today to explore making bodies and components for your next project.