DXF to STL – How to Convert DXF Files to 3D Printable STLs

Ask anyone who 3D prints, and they will tell you that STL files are the ones we look for. Slicers need them to create G-code, and we need them as an export format. The STL format is special because it can represent any 3D model using triangles.

Of course, there are more ways to represent a model other than triangles. DXF (drawing exchange format) is one of these ways. It was made by Autodesk alongside their proprietary DWG format. The intent behind this alternative format was to create a format open to everybody.

Having said this, DXF is not a simple format to convert from. The DXF format can contain and exclude information depending on the application used. This is why, when converting to STL, you should consider whether the DXF file you have contains 3D, or only 2D, information.

It may sound a bit convoluted, but to convert a 2D DXF to STL, you should first convert it to an SVG. SVG is a more widely used format for 2D drawings, giving you more options when it comes to converting a 2D drawing into a 3D STL model.

The simplest way to convert to SVG is to use an online converter such as DXFconverter. To use this converter, upload, convert, then download your file. Of course, you can always use a vector graphics editor, such as Inkscape, to simply “import” and “save as” an SVG file.

From here, feel free to follow our SVG to STL guide. Keep in mind that DXF files do not specify units and, thus, often require a scale factor somewhere in the process (more on this later in the article).

As mentioned previously, Autodesk created the DXF format. Therefore, the simplest way to convert to STL is to use their software. You can download a trial version of AutoCAD from their website. Follow along closely in order to convert your DXF to STL.

Step 1: Opening the DXF file

1. Open AutoCAD.
2. Ensure that you are using the 3D modeling workspace by clicking on the gear icon (bottom right).
3. Go to “Open” -> “Drawing”, and then select your file.

Step 2: Converting the file

1. Select your entire object by highlighting it with your cursor/lasso tool.
2. Go to “Mesh Tab” -> “Convert to Surface”.
3. Select your entire object again.
4. Go to “Surface Tab” -> “Sculpt”.

Step 3: Exporting the file

1. Go to “Export” -> “Other Formats”.
2. Select your desired location.

There is one final detail to cover: DXF does not always include units. This can make it difficult to print DXF files in the right size. In order to fix the size of your model, you can use a scale factor on your STL model. If you have a preferred size, simply divide the desired length by the current length of your model and use that as your scaling factor.

Featured image source: Caleb Favela / All3DP