Bodies vs components

[eamartin52]

In the case of a large assembly with many parts, and many parts not associated with any motion. 

Option 1. Make all stationary parts components, and assemble with rigid joints.

Option 2 leave stationary parts as bodies, use align and rigid groups.

In terms of computer resources, which method is better ?

[Haad_Ali]

Option number two is the best option if your prime purpose is just to align parts and their is no relative motion. 

[jeff_strater · Accepted solution]

some of this is personal preference, but I disagree - you are always better off with components and joints, in my opinion.  There is also a 3rd option - build everything "in place" and use As-Built joints (or Rigid Group, which is, itself, an As-Built joint) to create the joints.  This method is not as responsive to geometry changes, but if you don't expect to change the geometry, that should be fine.

[davebYYPCU]

Read trippys post on Rule No.1, including the exceptions. (Top section of this Forum)

You are mixing apples and oranges.

Bodies are a geometrical shape.

Components are a container - distinct section of the system, can have sketches, construction items, bodies and it's own Origin.  Each real world part - recommended to be Components.

Sheet Metal - Drawings, and CAM all require - As a Component.

Rigid Group is a Component Tool, and won't work on bodies not in a Component - (Top Level).

All components are free to move by accident until prevented, with Ground or Joint.

Option 1, If Components, ground them, one of the Rigid Group has to be, anyway.

Option 2, If Top level bodies - they are locked in position unless re-positioned, Rigid Groups not applicable.

For resources, can't comment.

Might help....

[eamartin52]

Hi Jeff,

Thanks for your input. I have a fairly good understanding of the reasons for components vs bodies. I was mainly curious about the impact on computer resources. 

On a similar note, I have seen many videos by many users. I notice that some prefer to do all sketches in top level creating multiple bodies, then in the end creating components. Do you have any thoughts on that?

[jeff_strater · Accepted solution]

from a resource point of view, there is probably not a lot of difference.  A component is slightly heavier than a body (in that a component has an origin, body folder, etc), but, on the other hand, if you have duplicate geometry, components can support instancing, where all copies of a component share the same geometry, so that is way more efficient.

"I have seen many videos by many users. I notice that some prefer to do all sketches in top level creating multiple bodies, then in the end creating components. Do you have any thoughts on that?"

That is certainly a valid workflow - sometimes referred to as "skeletal modeling".  This can be useful if you can establish inter-component geometric relationships in that sketch.  That workflow can be useful to build components "in place", which can then be connected with As-Built Joints (and because of the sketch, this can get around the limitation of not responding to geometry changes)