Data Management > Managing Heterogeneous CAD Data > About Opening TIMs or Derived CAD Documents
  
About Opening TIMs or Derived CAD Documents
When you open non-native CAD models with the File > Open command, the Creo application such as Creo Parametric creates derived CAD documents or the Translated Image Models (TIMs) of the CAD parts and assemblies. If a TIM exists for a non-native CAD model, you can open the existing TIM instead of creating a new TIM. The message area informs you if multiple TIMs exist for a source CAD model.
When you open an existing TIM, the atb_auto_check_on_retrieve configuration set to on by default, checks the ATB status of the TIM to verify if it is out-of-date or up-to-date with its source CAD model. The Creo application then adds the latest compatible CAD documents of the TIM and its dependents to the active workspace if they do not exist in the workspace. The primary content is added to the cache.
For CAD parts and assemblies:
The Import New Model dialog box displays the File name box.
If autonumbering is enabled, File name displays the model name with the autogenerated value from the server.
For assemblies, you must locate the CATIA, Creo Elements/Direct Modeling, SolidWorks, or NX model in the workspace or the commonspace to maintain its association with the imported components. You can search for their dependents in the following order of precedence:
The active workspace of the primary server.
The commonspace of the primary server.
The current working directory.
If you open a non-native CAD model, a TIM is created and its primary content and dependents are automatically added to your workspace and the cache. You can ignore this dependency or use the Auto-resolve options.
If you rename any of the dependents of the non-native assembly stored in a CAD document, you cannot retrieve the non-native assembly. You must synchronize or update the files to retrieve the assembly. If you retrieve the non-native assembly from the commonspace, then you must add the assembly and its dependents to the workspace.