JavaScript must be enabled in order to use this site.Please enable JavaScript in your browser and refresh the page. Working with a DGN File, Then Saving to a DWG File Start with a DGN file. You can open an existing DGN file, or create one. Develop your design in the DGN file. Choose File > Save As to save the DGN file to DWG format. Parent topic: Strategies for Working with DWG Data