Introduction
Is there still a place for 2D drafting in modern design and manufacturing? Depending on your processes and technology, the answer may be yes or no, but for many of us, it’s going to be somewhere in between. You don’t have to choose between 2D and 3D. We’d like to show you some tips, tricks, and workflows to use 2D drafting in AutoCAD and 3D parametric design in Inventor together.
Perhaps you are transitioning from one product to the other? Perhaps you are coming from AutoCAD to Inventor, and you want to re-use or repurpose some of the work you did inside AutoCAD inside Inventor? Or perhaps you are collaborating with colleagues who can only provide you with 2D details, and you need to convert them to 3D? Maybe it’s the other way? Maybe you work fully in 3D Inside Inventor, but your clients or customers are asking for 2D Drawings as a deliverable? Maybe you want to keep your survey drawings and site layouts in 2D, but you want to coordinate with mechanical designs that have been modeled in 3D? However you want to use 2D and 3D design, there is a workflow to help you.
IDW versus DWG
Did you know that you can open Inventor drawings in natively in AutoCAD? Autodesk Inventor was created by Autodesk in 1999. When it was first launched, it was decided to rewrite the rule book and create a brand-new drawing format for Inventor called .IDW. Of course, it was soon realized that customers expected Inventor to be able to open and work with AutoCAD data, and DWG was added as a drawing format. So, what’s the difference between IDW and DWG?
IDW files are native to Inventor. The file size is a little bit smaller and they load a little bit faster. The downside of IDW is that there are very few compatible programs for viewing or exchanging IDW data.
DWG files are native to AutoCAD, the file size will be a little bit bigger than IDW and they may take fractionally longer to open than IDW. The advantage of DWG is that the files will open natively in Inventor and AutoCAD, and there are many other programs and Viewers that are compatible with DWG data.
How do I choose which file format to use? If you never share data with others, use IDW. If you ever need to share data with colleagues using AutoCAD or many other CAD systems, you’ll find DWG is acceptable almost anywhere.
So, how do we create DWG files with Inventor? Inventor comes by default with both IDW and DWG templates. To create a DWG file in Inventor, you just need to select the DWG template.
Setting DWG as the Default Drawing Type in Inventor
If you want to permanently select DWG as your format you just need to select it in the application options:
Tools (Tab) > Options (Panel) > Application Options (Button)
In the application options dialog, look under the Drawings tab from the Default Drawing Type drop-down. Note that you can also set the DWG file version you want to use here.
Creating drawings in Inventor using the AutoCAD DWG file format follows the exact same process as IDW. There is no loss of functionality and nothing is missing.
To open the drawing in AutoCAD, you just need to close it In Inventor and open it in AutoCAD. It’s that simple.
So, what can we do with our Inventor DWG now that we have it in AutoCAD?
You’ll notice that you can’t change the Inventor model while you are in AutoCAD. That’s because the Inventor design model isn’t in AutoCAD; only the drawing is. So what else can we do?
Well, we can plot the drawing, take measurements, and add items such revision clouds and notes. This makes AutoCAD a great tool for anyone who wants to review our design electronically, but who doesn’t want the overhead of installing or learning how to use Inventor just to look at drawings.
But what if you need 2D AutoCAD geometry? That’s also possible, and we’ll get to it soon.
Insert Inventor Views into AutoCAD Drawings
We can’t edit the geometry in an Inventor DWG directly, but we can re-use 2D views. To do this, open an Inventor DWG file in AutoCAD and then switch to model space.
Gasp. There’s nothing there. And that’s okay. Unlike AutoCAD, Inventor has a modeling environment that is separate to its drawing environment. It references the model into the drawing a bit like AutoCAD uses x-references.
But if we open the AutoCAD block palette, we can see that all the model views that where created in Inventor are saved in AutoCAD as AutoCAD blocks. In fact, this is why an Inventor DWG is bigger than an Inventor IDW file: it contains two sets of data, Inventor data and AutoCAD data.
We can now insert the Inventor view into AutoCAD model space as a block. An example of when this could be useful is in facility or job-site layout. We can add an AutoCAD block that represents the footprint of our 3D model into our 2D layout. If we change the Inventor model, we just need to open the DWG file in Inventor to update the drawing, and then we can open it in AutoCAD again to update the view block.
Just be aware that if you copy and paste the view block into another drawing, the link will be lost and the block will no longer update. If you need this workflow, we encourage you to take a look at Autodesk Factory design utilities.
Try It
1. In Inventor, start the open command and navigate to ‘00 Inventor Drawing.dwg’ from the dataset (download the Material zip file to access).
2. Select the file with a left click and select the Options
button in the open dialog.
3. Select Defer updates, then click OK to open the
drawing. (This saves us having to share the full Inventor assembly.)
4. Take a look at the drawing in Inventor, then close the file in Inventor without saving.
5. From the dataset, open ‘00 Inventor Drawing.dwg’ in AutoCAD.
6. Navigate to paper space.
7. Take some measurements, add some annotations, or plot the drawing. What can you do with an Inventor DWG drawing in AutoCAD? What can’t you do?
8. Close the file without saving it.
Extra Credit
9. Double click over a viewport to enter it. What do you notice?
10. Exit the viewport and switch to model space. What do you see?
11. Start the Insert command (or open the block palette). Notice that the Inventor views are available to you in AutoCAD as blocks. Insert a view/block into model space.
12. Close the file without saving it.
Convert an Inventor DWG into an AutoCAD DWG (with Inventor)
So, we’ve learned that we can create drawings in DWG format in Inventor and open them directly in AutoCAD, but what we can do with that drawing is limited.
Let’s imagine that we’ve been asked to deliver a native, editable, 2D AutoCAD drawing as a deliverable. How do we do that? To create an editable DWG file, we’ll need to export the drawing.
To export an Inventor DWG to AutoCAD, Go to the Application menu (the orange tab with 'File' written on it).
Navigate to Export, then select Export to DWG. In the dialog, note that you can save your configuration and use it again. Click Next.
Look for Export options > Data scaling. Your Inventor drawing is drawn to scale on a virtual sheet of paper. The data scaling option allows you to choose how you want your drawing to come into AutoCAD.
You can choose whether the geometry will come into AutoCAD at the same scale as it was in Inventor or at 1:1 scale. You can also choose if you want the drawing to appear in AutoCAD’s model or paper space.
When you are ready, click Finish. When you open the file in AutoCAD, all geometry will now be in an editable 2D format.
For details of all the export to DWG options available to you, check out this resource.
Convert an Inventor DWG into an AutoCAD DWG (with AutoCAD)
If you only have AutoCAD, or you are just more familiar with the AutoCAD Interface, you can also convert drawings from Inventor DWG to AutoCAD DWG from inside AutoCAD. We will do this with the ‘EXPORTLAYOUT’ Command.
In AutoCAD, open an Inventor DWG file. Navigate to paper space. Right click over your layout tab and choose the option Export Layout to Model. Follow the prompts to create your editable 2D version of the Inventor drawing.
Notice that you don’t get any option to scale the Inventor drawing or remove the title block. You may need to scale the geometry if you want it to be a 1:1 and do a little clean up.
Try It
1. In Inventor, start the open command and navigate to ‘00 Inventor Drawing.dwg’ from the dataset (download the Material zip file to access).
2. Select the file with a left click and select the ‘options’
button in the open dialog.
3. Select Defer updates, then click OK to open the
drawing. (This saves us having to share the full Inventor assembly.)
4. Go to: Application menu (File) > Export > Export to DWG
5. Click Next
6. Under Export options > Data scaling, select Full scale (1:1) Model space.
7. Click finish and save your file. Close ‘00 Inventor Drawing.dwg’ without saving.
8. Open your exported file in AutoCAD to see what you got.
Extra Credit
1. From the dataset, open ‘00 Inventor Drawing.dwg’ In AutoCAD.
2. Navigate to paper space.
3. Right click over the paper space layout tab and pick ‘Export Layout to Model’.
4. Name and save your file.
5. Close ‘00 Inventor Drawing.dwg’ without saving.
6. Open your exported file in AutoCAD to see what you got.
Tip: There are example export files in the ‘05 Examples of Exported files’ folder. Compare the export from Inventor to the export from AutoCAD. Compare the location of 0,0,0, the scale of the geometry, the layers used etc. Which method suits your workflow best?
Create Drawings of Inventor Models in AutoCAD
There’s one more method of using AutoCAD and Inventor together that can give us the best of both worlds. At some companies, the tasks of 3D modeling a design and the creation of 2D drawings are done by different people.
This is an example where each user can use each program for what it’s best at, Inventor for 3D parametric modeling and AutoCAD for 2D drafting.
To do this we use a command in AutoCAD call Base View.
To create a drawing in AutoCAD from an Inventor model, we’ll use a command called Base View. Go to an AutoCAD drawing layout and start the base view command. You’ll notice that you can chose an AutoCAD model, or you can choose a model from Inventor.
If you’ve used the drawing environment in Inventor, the base view commands will look pretty similar. If you’ve used the drawing environment in Fusion 360, it will look even more familiar, because the Fusion drawing environment comes from AutoCAD.
We can add views, sections and details of the model, and add dimensions and notes. We can’t edit the model from here; we’ll need to do that in Inventor.
For more information on the base view command in AutoCAD, check out this resource.
We can also recommend J.C. Malitzke’s Autodesk University class:
Create Compelling 2D Sections, Details, and Auxiliary Views from AutoCAD 3D Models.
Want more? Download the full class handout to read on.
Paul Munford is a laugher, dreamer, bon vivant, CAD geek, and technical marketing manager for Autodesk in the UK. Paul's background in manufacturing items for the construction industry gives him a foot in digital prototyping and a foot in Building Information Modeling (BIM). Paul was a speaker at Autodesk University for the first time in 2012, and he says it's the most fun anyone can have with 250 other people in the room.
Luke Mihelcic has been involved with design, engineering, and analysis since 1995. His career started in telecommunications designing mobile production equipment for TV and radio. He has taught design and engineering at Pittsburgh Technical Institute and has spent over 10 years as an application engineer for an Autodesk reseller and Blue Ridge Numerics. His various roles as educator, end-user, and provider give him a unique perspective on identifying, understanding, and helping solve design and engineering challenges. As the technical marketing manager for the core manufacturing solutions at Autodesk, he is responsible for the development, creation, and implementation of relevant content and tools that help users understand and utilize the Autodesk Design and Manufacturing Portfolio.