About Attaching Coordination Models

A coordination model is a model used for virtual coordination of various trades through the pre-construction and construction phases of a project. It specifically refers to an NWD or NWC file. NWD and NWC are native file formats of Autodesk Navisworks. Autodesk Navisworks is used extensively to combine multidisciplinary design data into a single, coordination model.

Attach a Coordination Model to a Drawing

Attaching a coordination model to a drawing is much like attaching any other external reference. If the unit of measurement in the attached file differs from the units in the target drawing, the model is scaled automatically based on the unit type in the target drawing.

Note: Attaching a coordination model is not supported on 32-bit systems. To work with coordination models, you need a 64-bit system, and hardware acceleration must be turned on.

Control the Appearance of the Coordination Models

Use the following system variables that make it easier to differentiate between the drawing geometry and attached coordination models.

• CMFADEOPACITY. Controls the amount of dimming of all coordination models. Valid values are from 0 to 90. The higher the value, the more the model is dimmed.
• CMFADECOLOR. Controls the amount of black blended with all coordination models. Valid values are from 0 to 90. The higher the value, the more black is blended with the model.

Using Object Snaps

Object snaps provide a way to specify precise locations on an attached coordination model while creating your geometry. Coordination models support the standard 2D endpoint and center object snaps. If endpoint or center are set as running object snaps, a marker and a tooltip display when you move the cursor over these locations on an attached coordination model.

You can also specify object snaps any time you are prompted for a location. Hold down Shift and right-click in the drawing area to display the Object Snap shortcut menu.

Use the CMOSNAP system variable to turn object snapping for coordination models on and off.

Note:

• Geometry within the coordination model can contain nonstandard snapping points, such as circles with no center points. So object snapping may not behave the same as it does with AutoCAD objects.
• When working with complex models with many snap points, you may want to turn off object snap tracking (F11) or adjust the settings.

Support for object snapping to geometry in an attached coordination model is installed as a feature update for AutoCAD 2016.