Now I know I left my model around here somewhere…

Have you ever wondered why your DWG models appear as 2D lines (proxy objects) in Navisworks? If you've encountered this it's likely due to a missing object enabler.

So what is an Object Enabler?

You can think of an Object Enabler (OE) as a 'translator' for custom objects. Applications based on the AutoCAD platform, (including Autodesk products like AutoCAD Civil3D or AutoCAD MEP, and non-Autodesk products like CADduct or QuickPen) generate custom objects that are saved into the DWG file format. Many applications have the ability to read these DWG files, however outside of the authoring application these custom objects generally cannot be interpreted. DWG file readers will therefore tend to display these custom objects as proxy graphics - wireframe geometry as in the image above.

So for these custom objects to be displayed correctly outside of the authoring application, the OE is installed on the machine reading the DWG file, and this 'translates' the custom objects into a language that it understands. Simple when you know, but frustrating when you don't!

And what's a custom object again?

In this instance, a custom object generally refers to an object that can be selected and inserted into a file from within an AutoCAD-based application, such as a door, a duct, a pipe, a structural member, and so on. These custom objects are typically found in content libraries that are built into these applications.

So when is an Object Enabler needed?

An OE will generally be required whenever there is a need to read a DWG file containing custom objects, in an application other than the authoring application.

And how do I know if I need to use an Object Enabler with Navisworks?

When a DWG file is opened in Navisworks, if the objects are displayed as proxy graphics (as in the image above), then as a rule of thumb you're going to need an OE. Go to the Home tab and slide out the Project panel to access the Scene Statistics.

Which look like this:

Amongst other information, the Scene Stats will report any missing, or failed to load OEs. If you see these messages, it confirms that an OE is required to load the file correctly.

You'll need to install the relevant OE. Or, if the OE has already been installed and you still get these messages, then it's likely you're using a different DWG Loader version. I'll explain more about this and more in a follow up post. Stay tuned…