How to Export and Import Skeletal Mesh (Blender + Unreal Engine)

In this tutorial, you will learn how to export a Skeletal Mesh of a character in .fbx format from Unreal Engine to Blender.

After understanding the process, you will be able to make changes to the skeletal mesh in Blender and then import it back into Unreal Engine.

Although this process might seem simple, it caused me a couple of hours of errors and headaches. Therefore, I’m going to share this process with you so you can avoid the common “Failed to Merge Bones” error.

Let’s get started!

Export FBX in Unreal Engine

First, you need to export the Skeletal Mesh file.

To do this, simply right-click on the asset and select “Asset Actions → Export…“.

Next, save the file somewhere on your computer. The default export settings should work just fine.

This will export an .fbx file, which you can then open in Blender or any other 3D software.

Unreal Engine Export Asset

Export Skeletal Mesh FBX in Blender

To open the file in Blender, just click on “File Import FBX (.fbx)”.

Now, make the changes you want to the Static Mesh in Blender.

The problem is that if you simply click “File → Export → FBX (.fbx)” and leave all settings by default, you will probably encounter this error when importing the file back into Unreal Engine:

Failed to Merge Bones Unreal Engine Error

This warning message appears because Blender adds an extra bone to the skeleton.

When you import the skeletal mesh back into Unreal Engine, it might cause problems by modifying the original skeleton or creating a new one.

So let’s learn how to export the mesh correctly!


FAILED TO MERGE BONES:
This could happen if significant hierarchical changes have been made
e.g. inserting a bone between nodes.
Would you like to regenerate the Skeleton from this Mesh?

***WARNING: THIS MAY INVALIDATE OR REQUIRE RECOMPRESSION OF ANIMATION DATA.***

Blender Export Settings for Unreal Engine

The first and most important step is to ONLY select the items below the root bone.

DO NOT SELECT THE FIRST BONE.

Then, select “File → Export → FBX (.fbx)” and make sure the Include setting “Limit to Selected Objects” is enabled.

You can also use the default export settings that I usually use and that work fine:

  • Include Limit to Selected Objects: Enabled
  • Geometry Smoothing: Face
  • Armature Add Leaf Bones: Disabled
  • Armature Bake Animation: Disabled
Blender Export Settings for Unreal Engine

Import FBX in Unreal Engine

Once you have exported the FBX, you can import it back into Unreal Engine by dragging and dropping the file into the Content Browser, or by clicking the “+Add” button and selecting “Import to…”.

Then, the FBX Import Options window will open.

It is okay to leave everything as default, and then click “Import” or “Import All”, depending on your needs.

Unreal Engine FBX Import Options

Fixing the Mesh in Unreal Engine

It is possible that after reimporting the skeletal mesh, the materials are not correct, or that a new physics asset is created.

You can fix this by opening the skeletal mesh asset and selecting the correct materials in the Material Slots and the correct Physics Asset in the physics settings.

Also, you will notice that the first bone of the skeletal mesh is the root, as we selected in the export in Blender. If you selected the first bone during export, the skeleton will no longer match, and it will probably cause errors.

If you are curious about how I made this fox furry, check out our gFur plugin tutorial.

UE5 Skeletal Mesh Options

Hope this helps! Keep on creating!

Unreal Engine Learning Path