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Wieght Transfer from char to cloth using Blender - FAILED TO MERGE BONES Error

I was dealing with this problem the entire day and I am giving up in this moment.
This is the situacion:

I am making clothes in Marvelous Designer, and I am in the point where I want to transfer the painted weight from my character to that clothes, in order to import the cloth into UE.
For that Im using blender, following this:

(1) https://www.youtube.com/watch?v=d2_9uicFJXw

or

(2) 3d modelling - Transferring rig weights from one mesh to another in blender 2.76 - Stack Overflow

The two methods seems to be working just fine.

The problem is when I want to import what I did into UE, selecting the Pre existing Skeleton (the same that I use for transfer the weight, which IS exported from UE in first place), this message shows up:

**FAILED TO MERGE BONES:

This could happen if significant hierarchical change has been made

  • i.e. inserting bone between nodes
    Would you like to regenerate Skeleton from this mesh?

WARNING: THIS WILL REQUIRE RECOMPRESS ALL ANIMATION DATA AND POTENTIALLY INVALIDATE**

But as far as I know, I didnt modify any bone, I just did what is said in (1) or (2).

What could be happeing?
is there any other way to accomplish what I need?

Thanks!!

I don’t use Blender but I do use 3ds Max and make use of the Skin Wrap modifier a lot to do more or less the same thing of transferring the skinning weights and do run across this problem from time to time.

Assuming that you can export the character model just fine then the most common problem occurs when one Parents the mesh object to the bone hierarchy which in turn changes the bone structure as to being a copy of the original bones as imported into UE4. Watching the video I did noticed that you did Parent the chest plate to an armature which in turn creates this.

This is an easy fix as to the common practice of linking the clothing item to the character rig to make sure that it’s always align with the body origin but once the transfer is completed the object needs to be un-parented so that it is no longer included as part of the hierarchy and exported by selection assuming that once you have you bind pose set you no longer need it to be linked to the host rig.

@FrankieV to be honest with you, I didn’t expect a response, the question I made was pretty generic. But you nail it :slight_smile:
I ungrouped the cloth mesh as you said and only exported the cloth mesh (with the weight transferred) and the skeleton, I Imported the skeletal mesh selecting the character skeletal mesh and done.
As a note, when I did this an extra skeletal mesh was imported ( the cloth and character together), with no bones and no references. I dont know why that happens, but it can be deleted and done.

Thanks FrankieV! you saved my day