Fix Blink DNA Bone Expressions for Custom Meta Human

You sculpted a custom MetaHuman - maybe wrapped a whole new face onto MetaHuman topology - and now the blink is broken: the eyelids do not close, or they close in the wrong place, clipping through the eye. This is one of the most common problems with customized MetaHumans, and the usual advice is to fix the DNA in Maya. You do not need Maya. This guide fixes blink DNA bone expressions entirely inside Unreal Engine with the Mesh Morpher Poser.

Why blinks break on custom MetaHumans

MetaHuman facial expressions - including blinks - are largely bone-driven, defined in the DNA file. The expression bones were authored for the original face. Change the eye position or eyelid shape and the blink bones still travel their original path, which no longer matches your geometry. Corrective morph targets can patch small errors, but when the eye itself moved, the bones have to move.

The tool: the Poser

The Poser in Mesh Morpher Classic can bake skeletons, meshes and DNA expressions, create morph targets from poses, and generate correctives. For this fix, the key ability is editing the MetaHuman DNA expression bones directly and writing the result back into the DNA.

The workflow

1. Load your custom MetaHuman in Mesh Morpher and open the Poser.
2. Select the blink expression and inspect where the eyelid bones travel on your modified face. Mesh Morpher highlights the bones that belong to the DNA expression, so you can see exactly what moves.
3. Adjust the expression bone transforms so the eyelids follow your new eye position and close cleanly against the eyeball.
4. Bake the corrected expression back into the DNA. The fix travels with the character - it works in MetaHuman blueprints, Sequencer and packaged games.

The full process, from broken blink to baked fix, is in this video:

▶ Watch the video on YouTube

▶ Watch the video on YouTube

Tips

• Fix the eye components first. If the eyeballs, edges, lashes or shell drifted during sculpting, refit them with Relative Restore before touching the blink - otherwise you are aligning lids to a misplaced eye.
• Check both eyes and asymmetry. Custom faces are rarely symmetric; verify the left and right blink separately.
• Test at partial values. A blink that ends clean but clips halfway through still reads as broken - scrub the expression, not just its endpoints.
• The same method fixes other expressions. Squints, brow raises and any bone-driven expression that misbehaves after customization can be corrected the same way - see editing MetaHuman DNA bone expressions.

Going further

If you sculpted entirely new expressions and want the DNA to drive them with bones instead of heavy morph data, Mesh Morpher can generate bone-driven expressions from morph targets automatically. All of this works in Mesh Morpher Classic and in the standalone Studio app.