About Working with Assembly Family Instances

There are several points to remember when modifying instances of an assembly family. The generic assembly serves as the template for all instances; all of its components, assembly features, assembly dimensions, and characteristics are copied once each time an instance is activated. Then, when the instance is regenerated, components and features are blanked or substituted and dimensions are modified as indicated by the table.

You can modify parts in, and independently of, any assembly instance. There are two ways of modifying an assembly instance:

• Edit its Family Table. You can change a table dimension, turn an assembly feature or component on or off, or replace a component.

• Change it while it is in session in the active window. Then, when the instance is regenerated, the system automatically updates the generic geometry and Family Table.

You must observe the following rules when you are creating or using assembly families:

• If an instance of an assembly is in the active window and you assemble a component or add an assembly feature, that component or assembly feature is added as a new item in the assembly Family Table, but only for that particular instance. It is suppressed for the generic and all other instances.

• You cannot directly substitute components that are listed in the Family Table of the instance. To substitute a component, you must edit the Family Table and replace the component for the instance.

When the modeltree_show_gen_of_instance configuration option is set to yes the name of the generic displays as an extension of the instance name in the Model Tree. To open the generic or a different instance of the assembly or component in a separate window, right-click the instance in the Model Tree and choose Open Generic from the shortcut menu. Select the generic or instance to open from the Select Instance dialog box.

You can replace a component in an assembly Family Table with another component under the following conditions:

The automatic assembly of family members using Notebook requires a special procedure. You cannot make global declarations for the family instances. Instead, you can transfer declarations from the generic part to the instances.

To do this, you must retrieve the generic part and make the necessary global declarations before assembling an instance.