[3D Software] How to Export STL/OBJ Files from Various 3D Software

【3D Software】How to export STL/OBJ files in various 3D software

The most convenient way to turn a 3D model you painstakingly created in 3D software into a physical object is to print it directly using a 3D printer. However, 3D printers can only receive STL (Stereolithography) files, a format specifically designed for 3D printing. It can decompose the original curved or solid model into data of sectional shapes layer by layer. Most 3D software has the function to export to STL. So, how can you correctly export these file formats to avoid printing failures?
In this article, we will compile the export methods for various common 3D software, allowing everyone to complete the preparatory work faster and more efficiently when 3D printing!
(PS. Some software only has the option to export OBJ files. You can save as OBJ first and then convert to STL files.)
 
◎AutoCAD
◎3DS MAX
◎Solidworks 
◎Maya
◎Pro/ENGINEER
◎Rhino
◎SketchUP
◎Zbrush
◎Fusion 360

 
AutoCAD

Steps to export STL files

1. Click "Application" > "Export" > "Other Formats".
2. In the "Export Data" dialog box, enter the file name.
3. In "Files of type", select "Stereolithography (*.stl)". Click "Save".
4. Select one or more solid objects. All objects must be entirely within the positive XYZ octant of the World Coordinate System (WCS). That is, their X, Y, and Z coordinates must be greater than zero.
5. The .stl extension will be automatically appended to the file name.

※Additional notes
When exporting an AutoCAD 3D model as a .stl file for 3D printing, is the print quality not very good? As shown below:

In AutoCAD, changing the system variable "FACETRES" can adjust the fineness of curved surfaces.
The larger the value of FACETRES, the finer the result.
Because the default value of the AutoCAD system variable "FACETRES" is 0.5, many sharp angles appear as shown in the figure above.
You can increase the value of FACETRES (e.g., to 10), and the fineness of the print will significantly improve, as shown below:


3DS MAX

Precautions for exporting STL files
1. Application Menu > Export > StereoLitho (*.STL)

2. Object Name: Enter the name to save in STL format.
3. Binary/ASCII: Choose whether the STL output file is binary or ASCII (character) data.
ASCII STL files are much larger than binary STL files.
4. Select only the objects to be exported in the scene.

Solidworks

Precautions for exporting STL files
There is already a plugin that can directly export files to Cura! Please refer to this article for details.
(You can install the plugin from within Cura)

If you are using other slicing software, please continue below for conversion instructions.

Steps to export STL files:
1. Click File > Save As.
2. Select STL (*.stl) as the save type, then click Options.
3. Choose from the options described below, then click OK.
4. Click Save to export the file.
Export as
◎ Choose Binary or ASCII for the file format. Binary files are smaller than ASCII files, but some other systems do not support binary files. Choose the type supported by your target system.
◎ Units. Select the unit of measurement.
◎ Resolution. Controls the tessellation quality of non-planar surfaces exported in Stereolithography (STL) format. Lower error values produce STL files with higher overall part accuracy.
Files with higher accuracy (high tessellation quality) are larger and can slow down model calculation.
Rough or fine. Default resolution.

Maya

Steps to export OBJ files

1. In the drop-down menu, select Window → Settings/Preferences → Plug-in Manager, and a window will pop up.
2. In the C:/Program Files/Alias/Maya?.0/bin/plug-ins menu, find objExport.mll.
3. Check both the "loaded" and "auto load" options.
4. Then, go to File → Export All (export all) or Export Selection (export selected parts) in the drop-down menu.
5. Click the small square next to it → the Export All (Selection) Options window will pop up.
6. In the General Options, select OBJexport from the File Type drop-down, then click Apply.
7. Enter the file name and select the save path.
 
Pro/ENGINEER

How to export STL files
 
1. Click "File" in the menu, select "Save a Copy", a "Save a Copy" menu will pop up, select the folder to save the STL file, and select the file type to "STL", then click "OK".
2. Adjust the parameters of the STL file. In the pop-up "Export STL" dialog box, change the default value after "Chord Height" to "0", press the Enter key, the software will automatically change the chord height to the minimum value, click "OK" and the STL file will be successfully saved.
 
※Precautions for exporting files:
When saving STL format in Pro/E, the most important thing is the adjustment of parameters. The more reasonable the parameter adjustment, the more accurate the saved file, and the better the effect of 3D printing.
An STL file should save the coordinate values of the three vertices of a triangular planar facet and the normal vector of that facet. The magnitude of the normal vector is specified as 1, its direction points outward from the solid, and the saving order of the three vertices and the vector direction should satisfy the right-hand rule. Therefore, the more planar facets on the surface of an STL format model, the more precise the model.
However, more facets are not always better for 3D printing. Therefore, when converting to STL in Pro/E, you can directly change the default value after "Chord Height" to "0", press the Enter key, and the software will automatically change the chord height to the minimum value. Other values can use the default settings.

Rhino

Steps to export STL files
1. From the File menu, select Export Selected Objects or Save As.
2. The file type list in the pop-up dialog box will show the available file types for export.
3. Select STL. file in the File type field.
4. Enter a name in the File name field.
5. Set the saving method.
◎ Minimize save
◎ Save geometry only
6. If the exported file type has options, you can click the Options button to set them.
7. If the exported file type can only save mesh objects, the Mesh Conversion Settings dialog box for converting NURBS to meshes will pop up.

STL Export Options
File Type
1. Binary
2. ASCII
Export open objects
Adjust Mesh
STL Export Warnings
If the exported STL mesh is not closed, a warning message will pop up.
Must export
Save open meshes.

STL Mesh Export Check
Some rapid prototyping machines can only read completely closed (watertight) STL mesh files.
Before exporting a model as an STL file for expensive rapid prototyping output, it is best to confirm that the exported STL mesh meets the requirements of the rapid prototyping machine.

How to test if a mesh is watertight

1. Combine mesh objects.
Combine individual mesh objects into a polymesh.
2. Weld all vertices of the combined mesh object.
3. At the angle tolerance prompt, enter 180.
When the angle tolerance is set to 180 degrees, the Weld command welds all overlapping mesh vertices.
4. Execute the UnifyMeshNormals command.

Orient all mesh faces of the mesh object to the same side (outside or inside).
Use the SelNakedMeshEdgePt command to check if the mesh still has holes.
If any mesh vertices are highlighted, it means the mesh has holes at that location.

Avoid creating very large mesh files

◎ You can use the Mesh command, which is the same as the render mesh conversion settings in the file content. The difference is that the Mesh command creates a mesh that can be exported.
When exporting STL files from Rhino surface objects, the same mesh conversion settings apply. However, it is usually better to convert the object to a mesh first, inspect it, and then export it as an STL file.

◎ The best settings for converting different objects to meshes are not the same. Initially, you can cancel the maximum angle and maximum aspect ratio, and set the maximum distance from surface to edge (the maximum allowed distance between the midpoint of a mesh face edge and the surface) to the resolution of the rapid prototyping machine, which is approximately 0.005 inches (0.125 mm). After finding the best settings for your model and rapid prototyping machine, this process may become redundant, as you may become accustomed to using validated settings to convert NURBS objects to meshes.

◎ After creating the mesh, hide the NURBS object and use the FlatShade command to view the mesh without visual smoothing. If the mesh looks good, it can be exported as an STL file. If the mesh quality is poor, it can be deleted and a new mesh created with different settings.

◎When setting mesh conversion options, it is best to change only one setting at a time to compare the impact of that change. If most of the mesh looks good, but a small part doesn't, you can set the maximum aspect ratio to a value between 4 and 7. It is usually not worth setting the maximum distance from surface to edge to a value smaller than the resolution of the rapid prototyping machine.

SketchUp



Export STL files using extensions
To draw 3D graphics and print in SketchUp, you must install an extension to export STL files.
There are two ways to install extensions.
The steps for the first method are as follows:
1. Click "Extension Warehouse" on the toolbar.

2. The "Extension Warehouse" window appears. Click on "SketchUP STL".

3. The "Install" window appears. Click "Install".


The steps for the second method are as follows:

1. First, download the extension from the download page https://extensions.sketchup.com/en/content/sketchup-stl
The downloaded file will be sketchup-stl-2.1.4.rbz, where 2.1.4 may vary depending on the version.

2. Click the dropdown menu "Window" > "Preferences".

2. Click "Extensions" > "Install Extension", select the downloaded file sketchup-stl-2.1.4.rb, then click "Open".

3. When the following screen appears, click "Yes".

4. When the following screen appears, click "OK", then click "OK" again to close the "System Preferences" window.


5. Click the dropdown menu "File". If you see "Export STL...", it means the installation was successful.

 
Zbrush

Export as OBJ file
If the sculpted model is to be 3D printed, it must first be saved in OBJ format and then converted to STL format using other software.
First, click the Tool menu > Export button, then open the folder where you want to save the file, name it, and click the Save button, as shown in the figure.

 
[Hint]: OBJ files can only save one model and only the subdivision level currently being edited. If there are multiple objects in the SubTool panel, they need to be saved separately, or select the desired model and click the Save button.

Fusion 360




2. Export a single component or body
Right-click on the component or body name, select "Save as STL" from the dropdown menu, and the same panel as described above will open, but you can directly export a single component. Alternatively, use the "3D Print" function under the "Make" option in the top toolbar, and select the object you wish to export.

3. Export multiple solids as independent STL files
This can be achieved by creating groups. First, select "New Group" under the "Create" tool in the toolbar, and a small panel will appear. Then, select one or more solids, making sure to switch the option to "From Bodies" and select only one body before clicking "OK". After creating the group, it will be displayed at the bottom right. Then, add each additional solid to this group. Finally, right-click the group, select "Save as STL", and choose "One File" in the "Structure" panel.



Once the complete STL file is exported, you can import it into slicing software for settings and 3D printing! Want to 3D print but don't have a 3D printer? No worries, we also provide 3D printing services. Feel free to send us your files (remember to save them as STL files!) for evaluation!

References:
Autocad
Autocad

3DS MAX

Soildworks

Rhino

Sketchup

zbrush

Fusion 360