# Physics Asset Box Extents reading in Meters instead of CM (Blender FBX Import Scale Issue)

**URL:** <https://forums.unrealengine.com/t/physics-asset-box-extents-reading-in-meters-instead-of-cm-blender-fbx-import-scale-issue/2705939>\
**Category:** World Creation\
**Tags:** ue4-editor, unreal-engine, editor, question\
**Created:** [March 13, 2026, 2:03pm UTC](https://forums.unrealengine.com/t/physics-asset-box-extents-reading-in-meters-instead-of-cm-blender-fbx-import-scale-issue/2705939 "2026-03-13T14:03:55Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Ronniiyyy](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Ronniiyyy](https://forums.unrealengine.com/u/Ronniiyyy)\
**Post date:** [March 13, 2026, 2:03pm UTC](https://forums.unrealengine.com/t/physics-asset-box-extents-reading-in-meters-instead-of-cm-blender-fbx-import-scale-issue/2705939/1 "2026-03-13T14:03:55Z")

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UE 4.26

Hi everyone, I’m running into a frustrating scale mismatch between my Skeletal Mesh and my Physics Asset, and I’m hoping someone can point out what I’m missing in my Blender-to-UE pipeline.

**My Setup:**

- I rigged a custom vehicle in Blender.

- My units in Blender are set to Metric / 1.0 Unit Scale.

- I applied all transforms before parenting the mesh to the bones (Both the Mesh and the Armature have a strict Scale of `1.0, 1.0, 1.0`).

**The Problem:** When I import the FBX into Unreal Engine, the Skeletal Mesh looks perfectly fine. It sits in the world at the correct, realistic size.

However, when I open the **Physics Asset** , delete the default capsules, and create a new **Box Collision** around my `vehicle_base` bone, the scale is completely wrong.

- For example, my vehicle is physically 3 meters wide.

- In the Details panel for the Box shape, the Extent values show up as `3.0` instead of `300.0`.

- It seems the Physics Asset is reading the raw Blender meters instead of converting to Unreal’s native centimeters, which causes my vehicle to behave erratically (like flying or floating) when I simulate physics.

**My Question:** Why does the visual mesh scale perfectly, but the Physics Asset primitives are scaled down by 100? Is there a specific FBX Export setting in Blender (like `Apply Scalings: FBX All`) or an Import Setting in Unreal that I need to check to force the bones/physics bodies to recognize standard UE centimeters?

Thanks in advance for the help!

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<div class="post-metadata">

**Author:** ![brs-sebascova](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/brs-sebascova/32/1052483_2.png) [@brs-sebascova](https://forums.unrealengine.com/u/brs-sebascova)\
**Post date:** [March 13, 2026, 5:49pm UTC](https://forums.unrealengine.com/t/physics-asset-box-extents-reading-in-meters-instead-of-cm-blender-fbx-import-scale-issue/2705939/2 "2026-03-13T17:49:51Z")

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Hello there @Ronniiyyy!

Yeah, you are encountering a classic issue between UE and Blender, with scale mismatchs. What’s happening here, is that your mesh geo is using the uniform scale from export, while your skeleton probable has embedded/residual scale data from it’s original scale.

Please test the following settings, and try your import again:

- Transform:

- Armature

 ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/8/a/1/8a1cfdfb40551b58f72ca64e6cbe1c207f0c2c48.png)