What is the difference between a part (with 0 bodies in it) and a body?

Hello all! Currently, I am redesigning some icons for the assembly tree within GrabCAD print. As I work as a product designer over here at GrabCAD.

Some of my coworkers have told me that they want to visually see the differences in files for assemblies, subassemblies, parts, bodies, CMBs, STLs, OBJs, and VRMLs within the asset list of GrabCAD print.

I already know that assemblies contain subassemblies which contain parts that sometimes have bodies within them. So how is a part with 0 bodies in it, different than a body?

How can I illustrate the differences between a part and body in an icon?

2 Answers

A part with 0 bodies in it is empty. Maybe it just has sketches and other reference geometry, but otherwise, no actual surface or solid geometry exists.

A part with 1 body is typical for developed parts that are shipped off to suppliers to be manufactured. There are exceptions and times when a multi-body part makes sense for a developed part, such as an injection molded part that overmolds brass inserts.

A part with more than 1 body is typical for 'base parts' or 'master parts' used to drive downstream detailed parts aka 'top down design' methodology.

From my perspective, and the way my cad software treats them, parts and bodies are kind of the same thing. Icon-wise, here's some ways solidworks depicts multi-body related features.

1. intersect 2. combine 3. split 4. move/copy bodies 5. mirror

maybe this helps...

I'm not sure if this is universal within all CAD systems, but for the ones I work with:

a Part represents a single object. Parts contain one or more Bodies. Parts are saved as data files.

an Assembly represents a collection of one or more parts.

a Body is a sub-set within a Part, a group of geometric features. Bodies cannot be saved a individual files.

Sometimes, a multi-body Part can represent an assembly, where the bodies are the sub-components of the assembly.