# Updating FBX with new mesh with new blendsape, breaks FBX

**URL:** <https://ask.vrchat.com/t/updating-fbx-with-new-mesh-with-new-blendsape-breaks-fbx/26150>\
**Category:** Help!\
**Tags:** avatar, blender\
**Created:** [August 13, 2024, 9:43pm UTC](https://ask.vrchat.com/t/updating-fbx-with-new-mesh-with-new-blendsape-breaks-fbx/26150 "2024-08-13T21:43:55Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Zyphilux](https://yyz1.discourse-cdn.com/vrchat/user_avatar/ask.vrchat.com/zyphilux/32/3075_2.png) [@Zyphilux](https://ask.vrchat.com/u/Zyphilux)\
**Post date:** [August 13, 2024, 9:43pm UTC](https://ask.vrchat.com/t/updating-fbx-with-new-mesh-with-new-blendsape-breaks-fbx/26150/1 "2024-08-13T21:43:55Z")

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I am trying to add a new blendshape to this avatar to make the left arm really small as part of the toggle for the cool cyberpunk mantis arm. Right now it’s clipping as you can see from the image below, but my plan is to make a blendshape that will shrink the whole left arm really small so it looks like that section of the arm is replaced with the cyberpunk arm.

 ![1](https://global.discourse-cdn.com/vrchat/original/3X/2/c/2cc949327db906867596ec3da47cb6c3b514cc39.png)

So I imported the FBX from the unity project into blender. I use Blender 3.0.0 so that I can use CATS blender plugin, but I didn’t use CATS for anything with the avatar. These images below are my FBX export settings once I was done creating the blendshape key.

 ![2](https://global.discourse-cdn.com/vrchat/original/3X/b/0/b0e7c73844cc77a905bd02e70b853b754852fb2a.png)  
 ![3](https://global.discourse-cdn.com/vrchat/original/3X/3/7/370b88d0c475f8250bbded74aee5e252ea5422d8.png)

After that, I put the new FBX into my unity project and replaced the mesh in the skinned mesh renderer component, and now it’s skinnier than a pencil!

 ![4](https://global.discourse-cdn.com/vrchat/original/3X/e/e/ee5ad5c472301ba71a51df27ad461090a63fe8e6.png)

I’ve been trying to learn blender and unity for a couple months now, but there are still a lot of things I don’t understand, like these export options for example. So I am having a lot of trouble locating the issue.

Any help or advice would be greatly appreciated!

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**Author:** ![Spokeek](https://yyz1.discourse-cdn.com/vrchat/user_avatar/ask.vrchat.com/spokeek/32/48618_2.png) [@Spokeek](https://ask.vrchat.com/u/Spokeek)\
**Post date:** [August 13, 2024, 10:37pm UTC](https://ask.vrchat.com/t/updating-fbx-with-new-mesh-with-new-blendsape-breaks-fbx/26150/2 "2024-08-13T22:37:13Z")

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To match with the usual Unity export parameters from blender try the following:

- In the transform/Apply Scaling, select FBX Unit Scale (to fix the scaling issue from the fbx)
- Select the apply Transforms (just in case, to apply any modification being done)

If you also made changes to the armature (like bone creation or removal), maybe redo the armature within the rig menu of the fbx in Unity.

See if all of that helps.

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**Author:** ![docteh](https://yyz1.discourse-cdn.com/vrchat/user_avatar/ask.vrchat.com/docteh/32/12171_2.png) [@docteh](https://ask.vrchat.com/u/docteh)\
**Post date:** [August 14, 2024, 11:06am UTC](https://ask.vrchat.com/t/updating-fbx-with-new-mesh-with-new-blendsape-breaks-fbx/26150/3 "2024-08-14T11:06:19Z")

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Personally what I end up doing when I edit an avatars model is dropping the new FBX into the scene, and then using Pumpkin avatar tools to copy components from the original avatar to this new model.

> **[GitHub - rurre/PumkinsAvatarTools: A toolbox for easily setting up VRChat avatars in...](https://github.com/rurre/PumkinsAvatarTools)**
>
> A toolbox for easily setting up VRChat avatars in Unity. Adds functionality to the editor and automates some of the tedious tasks.

In the import settings for the model, set the armature stuff before dropping the model into the scene, so there will be an animator. Gets me every time, because pumpkin copies everything else.

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**Author:** ![Zyphilux](https://yyz1.discourse-cdn.com/vrchat/user_avatar/ask.vrchat.com/zyphilux/32/3075_2.png) [@Zyphilux](https://ask.vrchat.com/u/Zyphilux)\
**Post date:** [August 18, 2024, 12:36am UTC](https://ask.vrchat.com/t/updating-fbx-with-new-mesh-with-new-blendsape-breaks-fbx/26150/4 "2024-08-18T00:36:13Z")

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Those settings worked like a charm! Thank you so much!

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**Author:** ![Zyphilux](https://yyz1.discourse-cdn.com/vrchat/user_avatar/ask.vrchat.com/zyphilux/32/3075_2.png) [@Zyphilux](https://ask.vrchat.com/u/Zyphilux)\
**Post date:** [August 18, 2024, 12:42am UTC](https://ask.vrchat.com/t/updating-fbx-with-new-mesh-with-new-blendsape-breaks-fbx/26150/5 "2024-08-18T00:42:02Z")

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Thank you for this cool resource, I’m definitely going to give this a whirl!
