Extract Solid of Rhino .3dm Import

Is my geometry to complex for Revit or Dynamo to handle? I am trying to extract a solid geometry from and imported .3dm file.

I have confirmed in Rhino its a closed Polysurface

I have also run a test on a simple box object. Confirming Dynmao can extract import .3dm geometry.

Can you post your RVT and both 3dM files? You may need to call Element.Geometry instead, and build your solid from that. My guess is that the cube was a single extruded face where as that other shape looks like it may have been built differently (hard to see exactly what it is).


thanks for the reply. Element.Geometry comes up Null also.


The “dome” was created with a curve network surface, then offset srf as solid. then a cone shape cutout at the skylight, boolean difference

Dome.3dm (1.0 MB)

The box was created using the box tool. I just wanted to see if dynamo would extract .3dm geometry as i have only tested it in the past with .sat & .dwg files.

Are you in the mass family environment? If so that explains the issue of not seeing the geometry. Importing the massing family into a project environment enables geometry creation. Note that even after that this shape wouldn’t report as a solid as it’s not a solid in my Revit import - Revit can’t handle the types of shapes you built.

You may want to consider utilizing Rhynamo instead as it can read the breps which make up the solid buried in the 3DM.


I am definitely in the project environment. I wasn’t using mass at all. I tried import CAD with .3dm file as a generic model.

I did test your method with Rhynamo. Two issues came up. First, and probably more easily solved is scale. When import using the insert tool native to Revit it comes in at the proper scale. When i use Rhynamo show in the graph below it comes much larger. Its interesting because unlike import CAD you dont have the option to drive scale when importing .3dm

So when I use the Rhynamo tool i still get the geometry, I used that geometry to create a Generic Model Component. I still dont have the ability to analyze that geometry later. i can analyze the surface, as you can see its the only node that doesnt have a warning. That still doesnt help me achieve my goal of analyzing the volume of the solid. I think this Brep geometry is just too complicated for Revit to rationalize so it relies purely on surface geometry and doesn’t turn it into a solid.

The brep geometry imported into Revit loses the stitching between surfaces (see here for info on what I mean by this), as Revit doesn’t handle BREPs the way Rhino does. In fact from what I can see the Rhino model doesn’t handle breps the way you are asking - notice the initial rhino object in the Rhynamo node is a polysurface not a solid.

Out of curiosity (I’m not a Rhino user), do you have a volume when you select this as single object in Rhino?

I tried this a second time with Revit 2018.2. This version of Revit imported the geometry correctly, which was readable by Dynamo as well. Filtering so I got only the solid resolved the issue for me. .

If it’s not that it may be that the geometry didn’t import correctly in your Revit version. I question the version as my previous attempt was with 2017.2.3 which is where I got the “could not import all geometry” error. What version are you in? Can you post your .rvt if this doesn’t work?

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