Another cool solution but...
AN SKP file from Trimble 3DWarehouse (you must have a Gmail address )

Open the SKP file inside the free PCon Planner
https://pcon-planner.com

Export as OBJ format

Launch Obj23dmWireframe By Michael Gibson
http://moi3d.com/download/Obj23dmWireframe.zip
You will obtain a 3dm file format

As you can see some faces are not present but...