Mirroring flips your 3D model left to right, front to back, or top to bottom

When you mirror a STL file in Bambu Studio, you create a reversed copy of your model along one or more axes. This is useful when you need a left-handed version of something that was designed right-handed, or when you want to print two identical parts that face opposite directions. Bambu Studio has a built-in mirror tool that takes about 30 seconds to use.

The mirror function works on the model you have already loaded into your project. You do not need to edit the original file or use external software — the change happens only in your current print project, not to the file itself.

Key Takeaways

  • Open your STL file in Bambu Studio, right-click the model in the left panel, and select Mirror to see your mirroring options.
  • You can mirror along the X axis (left-right), Y axis (front-back), or Z axis (top-bottom), or combine multiple axes in one action.
  • The mirrored model appears as a separate object in your project, so you can position both the original and the mirror on the same print bed if you want.
  • Mirroring does not change the file on your computer — it only affects what you see and print in this project.

How to access the mirror tool

Start by opening Bambu Studio and loading your STL file into a new project. You can do this by dragging the file into the window or by going to File > Open and selecting your model.

Once the model appears in the 3D view, look at the left panel where your model is listed. Right-click directly on the model name or thumbnail. A menu will pop up with several options. Click on Mirror. A dialog box will open showing you three axes: X, Y, and Z.

Choosing which axis to mirror

Each axis controls a different direction. The X axis runs left to right, the Y axis runs front to back, and the Z axis runs top to bottom. When you mirror along an axis, the model flips in the direction perpendicular to that axis.

If you want a left-handed version of a right-handed object, you usually mirror the X axis. If you want to flip something front-to-back, use the Y axis. For most everyday prints, you will only need one axis. Check the box next to the axis you want, then click explore. The model will flip in the 3D view, and you can see the result when ready.

You can also check multiple boxes if you need to flip along more than one axis at once — for example, mirroring both X and Y will rotate the model 180 degrees while also reversing it. Experiment by checking different combinations and watching the preview until the model looks the way you want.

Working with both the original and mirrored versions

After you click explore, the mirrored model replaces the original in your project view. If you need to keep both versions on the same print bed, you have two options. You can undo the mirror (Ctrl+Z or Cmd+Z), then load the same STL file a second time into the project. Now you have two copies. Mirror one of them, and position them side by side on the bed.

Alternatively, you can load the file once, mirror it, then use File > Import Model to add the original back in. This way you end up with both versions in one project, and you can arrange them however you need for printing.

Saving your mirrored model

The mirror change exists only in your current Bambu Studio project. When you close the project without saving, the mirror is lost. If you want to keep the mirrored version, save your project file (File > Save Project). This saves the arrangement and settings, not a new STL file.

If you want to export the mirrored model as a new STL file that you can use in other software or projects, right-click the mirrored model in the left panel and select Export Model. Choose a location and filename, and Bambu Studio will save it as a standalone STL file. This new file is the mirrored version and can be opened in any 3D software.

Undoing a mirror if you change your mind

If you mirror a model and then decide you want the original orientation back, press Ctrl+Z (or Cmd+Z on Mac) to undo. This works as long as you have not closed the project. If you have already closed and reopened the project, undo will not work — you will need to load the original file again or re-mirror to flip it back.

There is no "undo mirror" button in the menu, so keyboard shortcut is the fastest way. If you are unsure whether a model is mirrored, rotate it in the 3D view and compare it to what you expect. Text or logos on the model will appear backwards if it has been mirrored.

Common reasons the mirror does not look right

Sometimes a mirrored model looks wrong because you mirrored the wrong axis. Rotate the model in the 3D view by clicking and dragging with your mouse to see it from different angles. This helps you figure out which direction you actually need to flip. Undo and try a different axis.

Another common issue is that the model was not centered at the origin when it was created. This can make the mirrored version appear in an unexpected location on the print bed. You can drag it back to where you want it, or use the Arrange function (right-click the model and select Arrange) to auto-position it.

Frequently Asked Questions

Does mirroring change the size or shape of the model?

No. Mirroring only reverses the direction. The dimensions and shape stay exactly the same — only the orientation changes. A model that is 10 mm wide will still be 10 mm wide after mirroring.

Can I mirror just part of a model?

Not with Bambu Studio's built-in mirror tool. The mirror function works on the entire model at once. If you need to mirror only a section, you would need to edit the STL file in a 3D modeling program like Fusion 360 or Blender before importing it into Bambu Studio.

What if I mirror a model and then want to print both the original and the mirrored version?

Load the STL file twice into your project — once as the original and once mirrored. Position them both on the print bed, and Bambu Studio will print both in a single job. You can also mirror one and keep the other as-is.

Will the mirrored model print differently than the original?

No, assuming your printer is working correctly. A mirrored model prints with the same quality and strength as the original. The only difference is the direction it faces. Some models may need different support placement after mirroring, so check the preview before you start the print.

Can I mirror a model that has already been sliced?

No. Once a model is sliced, it becomes a toolpath file, not a model. You must mirror before slicing. If you have already sliced, undo back to before the slice, mirror the model, and then slice again.