Integration with Other Applications > Managing CAD and Part Structures in Windchill > Top-down Design > Building the CAD Structure from the Part Structure
  
Building the CAD Structure from the Part Structure
You can use a reverse build operation to reconstruct a CAD document structure based on changes made to the related part structure.
A build operation is performed using one of the following actions available in the tool bar of the Compare Part to CAD Document window.
Action
Description
Build one level CAD structure
Builds the CAD document structure for selected assembly parts.
Build multi-level CAD structure
Builds the CAD document structure for selected assembly parts as well as subassemblies used by the selected parts.
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• First compare the CAD document structure to the part structure to verify that the edited part structure is correct and that the appropriate build status has been set. For more information, see Setting Build Status.
• If you modified the Windchill part usage link, you can choose to update the CAD document usage link during the CAD structure build process. This behavior is only supported for CAD documents created using CATIA V5, NX, and PTC Creo (versions 2 and greater). For more information, see Updating CAD Document Usage Links.
To perform a reverse build operation:
1. Select the assembly to be built and click the Compare icon in the Structure tool bar on a part information page.
2. Select Compare to CAD Structure from the drop-down menu. The Compare Part to CAD Document window is displayed in occurrence mode. In other words, the window displays one row for each part occurrence used in the assembly.
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The parts must be checked in and a workspace must be selected when the Compare Part to CAD Document operation is launched in order to use the build actions.
3. Examine the comparison between the part structure and CAD document structure and change the build status accordingly.
a. The Build Status column in the part structure pane on the left shows what parts have already been built in the CAD document structure (Build Status equals Completed), what parts will be bypassed by the build process (Build Status equals Excluded), and what parts will be used to create the equivalent CAD document structure (Build Status equals To Be Built).
b. If desired, change the build status in the compare window by selecting an occurrence and choosing the Set for Build action in the right-click menu.
4. Select the assembly to be built in the part structure on the left side of the Compare Part to CAD Document window.
5. Click the Build one level CAD structure icon or Build multi-level CAD structure icon.
The part structure is refreshed and the build status changes on the part occurrences selected to be built. Parts previously labeled To Be Built now have a build status of Completed. Part occurrences that were omitted from the build process retain the build status Excluded.