Solid Edge offers two basic ways to design an assembly: top down and bottom up. Bottom up design refers to building individual components separately and then putting them together to build a final overall assembly. Top down assembly modeling is an assembly-centric method, which starts at the highest level possible—individual parts and sub-assemblies are defined within the context of the overall assembly.
To help you with planning top down assemblies, and to make building assemblies faster and easier, Solid Edge provides a suite of commands and tools, such as virtual components, copy-sketch, assembly-based features, assembly sketches and, perhaps the most versatile feature of all, create part-in-place.
The 'Create Part In-Place' command allows creation of new parts, or subassemblies, within the context of the assembly. Once started, it prompts to specify the location to save the new file—simply type in a name and click Save. The new component is immediately added to the PathFinder.
There is an option on the create-in-place dialog to immediately take you into the component after creating it to begin to model geometry.
The advantage is that you can create geometry by referencing the background components of the assembly to ensure proper fit and function. You can toggle the display of the overall assembly in the background by pressing CTL+Q.
When defining the location for the new part, select a point where you wish to begin the design. The 'Project to Sketch' command helps in creating new 2D geometry by referencing elements from the existing components of the main assembly.
You can also use the offset command to add more geometry without having to actually create new 2D entities explicitly. This gives you regions, which you can select to produce 3D objects for the new part.
Next, you can continue using regular 3D part editing commands, such as adding rounds on the part still within the context of the assembly. You can use the Ctrl+Q key combination to quickly hide the main reference assembly, or to bring it back into view when commands are complete.
This top down assembly modeling approach in Solid Edge reduces the design cycle length and eliminates fit errors by taking better advantage of common part geometry.
Check out the video below to see top down assembly modeling in action: