3D Printer: What Programs Are STL Files Edited with?

There are many file formats that can be used when printing in 3D. Some of them are: OBJ, AMF, 3MF, STL. In this article, we will provide information about the STL format editing and STL editing programs that are frequently used.

What is an STL File?

In summary, an STL file stores information about 3D models. This format describes the surface geometry of a three-dimensional object only without any representation of color, texture, or other common model attributes. These files are usually created by a computer-aided design (CAD) program as a final product of the 3D modeling process. “. STL" is the file extension of the STL file format. The STL file format is the most widely used file format for 3D printing. When used in congenido with a 3D slicer, it enables a computer to communicate with 3D printer hardware. Since its early days, the STL file format has been accepted and supported by many other CAD software packages, and today it is widely used for rapid prototyping, 3D printing and computer-aided production. Hobbyists and professionals use this system in the same way. stl editing programs

What is STL File Explosion?

The actual meaning of the file extension . The STL has disappeared into the mists of time. It is believed to be an acronym for the word stereolithography, but it is sometimes referred to as "Standard Triangular Language" or "Standard Tesslash Language". The main purpose of the STL file format is to encode the surface geometry of a 3D object. We name this information using a simple concept that we will define as "mosaicization" in the future as "mesh". stl editing programs Tesslashing is the process of overlapping a surface with one or more geometric shapes or laying it so that there are no gaps. If you have seen tiled floor or wall, this is a good example of real life to Mosaic.

Invention of STL File Format

In 1987, Chuck Hull invented the first stereolithographic 3D printer, and the Albert Consulting Group for 3D systems was trying to find a way to transfer information about 3D CAD models to a 3D printer. They realized that they could use mosaics of the surface of the 3D model to encode this information. stl editing programs Since the invention of the mosaic structure, it has remained the de facto standard in the 3D printing industry. Despite the years, most 3D printing in our age continues to use STL format due to its strong support in every software and hardware in the 3D printing tool chain.

What are the Features of STL Format?

STL is one of the simplest open source file formats. Supports both ASCII and "binary" encodings.The STL can encode the geometry of a 3D model, but it cannot store information about the object's color, textures, or materials. stl editing programs Until recently, most 3D printers were able to print models with only one material. Therefore, only a file format that stores geometry was sufficient. In the last few years, multicolored 3D printing has rapidly become widespread. Therefore, STL files are no longer available on printers that print in color 3D. stl editing programs The basic idea is to mosaicize the 2D exterior of 3D models using small triangles (also called "facets") and store information about the facets in a file. Let's look at a few examples to understand how this works. For example, if you have a simple 3D cube, it can be covered with 12 triangles, as shown in the picture above. As you can see, there are two Triangles per face. Since there are six sides of the cube, it goes up to 12 triangles. If you have a 3D model of a sphere, then it can be covered with many small triangles. stl editing programs Albert Consulting Group for 3D Systems realized that if they could store information about these small triangles in a file, it could fully identify the surface of an arbitrary 3D model. This formed the basic idea behind the STL file format. Triangles can be made small in curved areas. However, the smaller the triangles, the greater the number of triangles required to cover the surface. Having a large number of triangles means storing a lot of information. This can lead to large file sizes. stl editing programs It is the original sphere with a smooth surface on the left. Large triangles are used in the sphere on the right, which offers a rough model with a small file size. Smaller triangles are used in the middle sphere and offer a much larger file size and a smoother surface. Therefore, it is extremely important to find the right balance between file size and print quality. It does not make sense to reduce the size of the triangle too much, since at some point the human eye will not be able to distinguish the nature of pressure anyway. Most 3D drawing programs offer several settings when exporting STL files. These settings determine the mosaic size of the front faces and therefore the print quality and file size.

Where to Download STL Files?

One of the strengths of the 3D printer STL model is that there is no shortage of downloadable models and supporting software.There are many warehouses and search engines online that include literally millions of free 3D printer STL models. You can find our related article here. stl editing programs

STL Imaging Programs

There are several free STL file viewers that you can use online or as a desktop application to view an STL file. For this purpose, you can try ViewSTL online and GLC-Player as a desktop app for free. You can also view STL files with the "Print 3D" app available in Windows 10. stl editing programs No additional programs are needed to view STL files on computers running macOS. With the Preview app installed, you can open it directly to view STL format files. However, if you also want to use a program, you can use Pleasant3D as an alternative.

How to Fix Corrupted STL Files

Since the STL file can be opened unprotected, there is nothing to prevent you from changing the contents of a file using software such as FreeCAD. There are several programs that can help fix a corrupted STL file. For example, you can use the Meshmixer program for free. Other programs where you can edit STL files: FreeCAD Meshmixer Fusion 360 SketchUp Solidworks Siemens NX CAD Blender MeshLab 3D Slash SculptGL Microsoft 3D Tools 3D Builder MeshFix Open3mod Online and free STL file editors: Trinckle 3D Tools stl editing programs

STL Repair with Netfabb

Netfabb is a powerful tool for fixing STL files. You can download the trial version of Netfabb, which only works on Windows, here. After registration, you can use the full 30-day version. Compared to Windows' own app, 3D Builder, Netfabb can repair STL files, detect parts with fine details, and optimize the 3D model accordingly.

Import Corrupted STL File

After installing Netfabb, click File -> Open Part from the menu. You will see a settings panel that offers various alternatives to import the part. Use the default settings and add the 3D model by clicking "Add Parts". stl editing programs If the STL file is corrupted, you will see a very large red exclamation point in the lower right corner. This means that you need to correct the STL file. If the exclamation point is not visible, it means that the part is good and can be printed without problems.

Fixing the STL File

To fix the STL files, open the repair tool indicated by the red "+" on the top toolbar. At this point, Netfabb creates a copy of the 3D model that you installed. The process of repairing the STL is applied on the copy of the model and ensures that the original model is not replaced. On the left side you will see the Repair Panel. The Fix panel tells you about the following important features:

  • Is there a mesh closed or a gap?
  • Is the mesh properly directed?
  • How many edges are there?
  • How many triangles are not oriented as expected according to neighboring triangles?
  • How many empty holes are in the 3D model?

In the Correction panel, click Run Repair Script, and then select Default Repair in the pop-up window that appears. If the default Fix fails to repair the model, you can try Extended Repair later. Click Execute to run the correction process. stl editing programs If the process of repairing the STL results well, the Correction Panel will show that the mesh is now closed and is properly routed with two green check marks displayed. You can also check for remaining edges, misdirected triangles, or empty holes by reaching out to the Correction Panel.

Optimizing the STL File

Netfabb allows you to optimize the STL file even if it is corrupted. When in correction mode, choose Edit Mesh and Reduce Triangles from the top menu. Be sure to select All Triangles in the options in the window that appears. For other settings, the default values usually work quite well. Netfabb's optimization routine is essentially better than the 3D Builder, since it can automatically detect low and high-detail parts and optimize the file accordingly. This ensures that you do not accidentally lose the details in the model due to optimization. When it's ready, click Reduce. Now approach the model and check if you are satisfied with the final result.

Saving an Optimized and Fixed STL File

To save the corrected 3D model, click File and select Export Part. The great thing about Netfabb is that it allows you to save the corrected track in multiple formats. To print the 3D model, save it in STL format. stl editing programs

STL Repair with Windows 3D Builder

For Windows users, the 3D Builder app is the easiest tool to use to automatically detect and repair errors in STL files. 3D Builder comes installed with Windows 10, so you don't need to install anything. You can find the app from the search bar by clicking the lens icon at the bottom left. If it is not installed on your computer, you can install it for free here.

Importing Corrupted STL Files

When you open 3D Builder, you will see a window as you can see in the picture below. From there, click Open, and then click Load Object. Select and install the STL file. stl editing programs In this example, you can download the defective STL file we use from the Thingiverse site.After installing the 3D model, you will see it on the working plane. The model was installed at this stage, but has not yet been imported. To import, click Import Model from the menu at the top.

Fixing the STL File

After the model is imported, the 3D Builder will automatically notify you of all defects in the model below right, as you can see in the picture below. In the event of a failure, the pop-up window says " One or more objects are invalidly defined. Click here to repair it." stl editing programs If a warning does not appear and the object has a blue line, it means that 3D Builder has not encountered any problems with your file. You can process the STL file with slicing software and print it directly to the 3D printer. If there is a pop-up window that contains the error message and you click this pop-up window, 3D Builder automatically corrects the STL file. After the model is corrected, a blue outline appears around it.

Optimizing the STL File

Sometimes, you may want to optimize the STL file to have fewer triangles and therefore smaller file size. 3D Builder offers simple ways to optimize an STL file. stl editing programs From the menu at the top, click Edit and select Simplify. It has a Reduction level adjuster that controls the amount of optimization. If you make this adjustment too much and you may lose the fine details in the model. If you do too little, you may not be able to reduce the file size enough. It's important to play with this tuner and zoom in on the thinner parts of the models to ensure that the optimization routine doesn't destroy the finer details. After setting the throttling level, click Reduce faces. If a red rectangle appears under the optimized part, there are errors. In this case, you should repeat the process of repairing.

Saving an Optimized and Fixed STL File

To save the corrected and optimized model, click the 3 line icons in the upper left, and then click "Save as" in the column that appears later. Save the model as STL again. stl editing programs

How to Make Changes to the STL File

"With which programs does the STL file open and how do I edit it?" is a question that any 3D printer owner will eventually wonder. The ready-made 3D printer STL files you downloaded are fine, but what can you do if you want to work on the model and add different features? Editing STL files can be done with two different modeling software:

  • CAD Software (Computer Aided Design): Specially designed for modeling. CAD tools were not designed for 3D printing in the first place. For example, when you draw a circle, it is a real circle. However, in STL files used for 3D printing, circles are represented as polygons. Therefore, CAD tools cannot do everything when editing STL files. Of course, they can be used to work with STL files.
  • Mesh Editing Tool: There are mesh editing tools such as MeshMixer and MeshLab. Models are designed for objects represented by animation and a 2D surface. These objects have only one shell and are not filled with them. This can cause walls too thin to be printed on a 3D printer if the object is not filled in and converted to a solid model (this can be done easily in tools such as the Meshmixer). In fact, mesh editing tools are excellent tools when it comes to editing STL files.

Converting an STL File

Converting G-Code to STL

G-Code files are commands that tell a 3D printer how to print a 3D model. G-Code usually defines printer parameters such as speed and temperature and the geometry of the 3D model. Typically, STL files are converted to G-Code files using a slicer such as Cura. However, it is much less applicable to turn G-Code back to STL. The main reason for translating G-Code into an STL file is that the 3D model does not have the original STL file. It is possible to encounter errors during the conversion of the format. For example, G-Code files also contain codes for support structures that are typically used in 3D printing. When converting to G-Code STL, support structures remain in the new STL file, and something completely different may also occur from the original STL file. In 3D model editing software, you may have to manually clean those supports one by one.

There are two simple methods that can be used to convert a G-Code file to an STL file without requiring any action.

Online G-Code STL Converter: MakePrintable

MakePrintableis an online 3D printing editor. It is a website that publishes repairs, printing and models. MakePrintable converts the ".gcode" files that you have installed to ".stl" files. You just need to be a member of the MakePrintable site to perform the conversion.

Then, go to the "Labs tab" tab and click Start in the G-Code converter (reverser). After you install the G-Code file, select Quick Repair or Run Workflow. Quick Fix is the best option for beginners who want to get a quick result. However, especially for laborious conversions, it is possible to increase the success of the conversion process by creating Customized Workflow.

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Voxelizeris the slicing software used in Z-morph 3D printers. Voxelizer has an integrated ability to convert G-Code files to STL files. This capability works by converting the 3D model into "voxel" and "voxel" elements that define it. A voxsel can be of any size, but the smaller the voxsel, the better the resolution of its model. stl editing programs To convert a G-Code file to STL, open the Voxelizer program. Click File -> Import, and then select the G-Code file. When the G-Code file is displayed, select the voxelize icon at the top left of the screen, and then select "Voxelize".

Next, you will need to set a vocsel size for vocselization. The 0.1 mm option is usually good if you do not set the layer height lower than 0.1 mm. Ideally, matching or reducing layer height with your vocsel size will give the best results. After the operation is complete, save the file as STL.

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Converting an STL to STEP

A STEP file is a cad file format commonly used for 3D models as standard for product model data. STEP files can be easily transferred from one CAD program to another.

Convert STL to STEP with Fusion 360

A simple method of converting STL files to STEP files is to use Autodesk Fusion 360. To do this, first upload an STL file to fusion 360.

  1. Go to the Data panel and select a subfolder to upload the files.
  2. Then press Upload to select the STL file you want to upload, and then press select files.
  3. Then press the Upload button and wait for the installation to complete.
  4. When this is complete, export the file by clicking File -> Export.
  5. From here you can select various file types, including STEP to export.

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Convert STL to STEP with FreeCAD

FreeCAD is a free alternative CAD program where you can convert STL files to STEP files. First, you need to upload the STL file to FreeCAD.

  1. Click File -> Open and select the STL file.
  2. After the model is installed, select View -> Panels -> Tree View and make sure that the tree view panel on the left, where the model's details appear, is open.
  3. Make sure "Part" is selected in the pop-up menu at the top center of the screen.
  4. With the file name selected in the tree view on the left (where CSG is written in the image above), select Part -> Create shape from mesh, leave tolerance as 0.1 default, and press "Ok".
  5. Save the STEP file by pressing File -> Export.

stl editing programs

Converting STL to DXF and DWG

DwG files, which are basically autocad'snative file format, store 2D and 3D vector image data and are highly compatible with other CAD software. Therefore, it is one of the most frequently used file formats in many industries.

Convert STL to DWG with Blender

There are several ways to convert STL to DWG file, but one of the easiest ways to do this is to use Blender. The software helps you open STL files and transfer them to DXF, a file format compatible with all versions of AutoCAD. You can then open this DXF file in AutoCAD and save it as a DWG file.

  1. Open the STL file in Blender.
  2. Click File -> Export. Select AutoCAD (.dxf) and save it.
  3. If the DXF option is not active in the export, go to User Preferences (via Ctrl / Cmd + Alt + U shortcut on Mac IOS) and type "DXF" in the search bar. Enable the Import-Export option.
  4. After saving the file as DXF, open it in AutoCAD and save it as DWG.

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Converting STL to OBJ

OBJ files are more flexible for storing a large number of small triangular structures and can use freeform curves as different polygons. OBJ can store color and texture information in its files, making them ideal for multicolored 3D printing.

In general, STL's are mainly used in 3D print slicers (such as Cura) or modeling programs (such as fusion 360), while OBJ files are more universal among the little-used CAD programs of the 3D printing world.

Online Converter: MeshConvert

One of the simplest ways to convert an STL file to OBJ is the MeshConvert converter site used online.

This site allows you to convert STL file to file formats such as OBJ, DAE, PLY quickly and free of charge. This method allows you to convert ready-made STL files downloaded from Thingiverse to OBJ files without the need for a program.

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Turn STL into OBJ with Blender and Fusion 360

Another easy way to convert an STL file to OBJ is through modeling programs. Most CAD programs, such as blender or Fusion 360, can import and export both STL and OBJ files.

Converting an STL to A G-Code

So how to print an STL file to a 3D printer? After designing and registering the model as an STL file in 3D modeling programs (CAD), you can convert STL to G-Code with slicing software.

Select parameters that suit their needs and 3D printer, adjust the size and quality settings, press "Slice".

stl editing programs

Other Programs That Convert the STL File