Integration with Other Applications > Managing CAD and Part Relationships in Windchill > Building CAD and Product Structure > Build Rules and Build Links
  
Build Rules and Build Links
Build rules are used by the Windchill build service to create or update CAD and Windchill product structures. In CAD-driven design, the build rules determine how a the CAD structure builds a corresponding a product structure, as determined by the relationships (build links) between the CAD documents and their associated parts.
Build links are the structure, attribute, and representation “building blocks” described in the topic Association Types for CAD-Driven Product Design. They define the build rules that correspond to the association types that you assign in the Windchill user interface. An exception is the Content association type, which has no build links and does not participate in the build process. The characteristics of the association types are summarized in the topic, Comparing CAD and Part Association Types.
The Owner association type specifies that you want to pass all the children of a CAD document to its corresponding Windchill part. For this to work, each child must be associated with a corresponding Windchill part that has at least a Representation build link in its build rule. This is because an Owner association has a structure build link as part of its build rule, as shown in the following table.
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When you specify a structure link, the Association user interface allows you to choose one, or several EPMMember links to copy to the part structure. Only the immediate EPMMember links of the selected CAD document are presented in the user interface.
The following table lists the association types and identifies the build links incorporated in their corresponding build rules.
Association Type
Build Links in the Build Rule
Owner
Structure
Attribute
Representation
Contributing Image
Attribute
Representation
Image
Representation
Contributing Content
Attribute
Content
Not applicable (not a participant in the build process).
The Auto Associate and Edit Association actions prevent you from creating or associating a CAD document if:
it is an unsupported Representation type of association; for example, attempting to create a second Owner association or a second Contributing Image association to a Windchill part.
the CAD document is manually flagged to not associate. For more information, see Controlling the Associations Formed by Auto Associate.
Prior to Windchill 9.1, a build took place whenever a CAD or Windchill product structure was checked in. Currently, you can delay the build of a modified structure until ready to commit the changes. During the build, if the structure has changed, then the corresponding part is iterated. However, if the structure has not changed, the build service does not iterate the part.