Why does my Blender skeletalmesh have incorrectly scaled physics?

I am having trouble importing a skeletal mesh from blender3D. I tried to find a solution online but nothing similar appeared in my searches.
The mesh itself looks right, but when I add a physics asset to it, this is what happens:

The scale of the collisions is completely wrong, no matter what I try.
I tried selecting everything in blender, and scaling it, then exporting, tried exporting it with scale 1.0 (but then I can’t scale the skeletal mesh inside UE4 anyways, and the collisions for the wheels are never created)

I’m assuming the wheels are too small and it only creates a tiny dot as a collision

Is there something that I’m missing?
should I add this to the official importing from blender3D thread?
Is this something that will be fixed in 4.2?

Please take into account that I’m a noob at blender3D

Hi stromchin,

Usually with something as complex as a vehicle, the collision would be created in a 3D program (Blender in your case) as a custom mesh and then imported into a game engine. Once in the engine it would be applied as the collision for the vehicle.

For a bit of info on this please take a look at the Collision section of this documentation: FBX Static Mesh Pipeline in Unreal Engine | Unreal Engine 5.1 Documentation

I hope that helps.

Thanks, TJ

I already read all of that. And tried using UCX_bonename
etc but that seems to be only for static meshes, not skeletal meshes.
I followed this tutorial:
Vehicle Modeling/Rigging Tutorial in Maya for Unreal Engine 4 - YouTube


combined with this one for blender3D

and this is the part that doesn’t work anything like my mesh imported from blender
Unreal Engine 4 Vehicle Tutorial (Blueprint) - YouTube

The imported bones are too small and the “single convex hull” creation fails miserably, creating just one mesh for the main bone, and drawn at 1/50th of the actual car scale, and ignores the bones in the wheels.

I would love to be able to set up the collisions in blender itself, but like I said, the UCX_ UBX_ USP_ seems to be working only with static meshes, not skeletal meshes.

Hi stromchin,

I was just checking up to see if you have solved this issue yet?

If not please feel free to post a link to the FBX and we will take a look at it. If you’re not comfortable posting it here, you can send me a link through Private Message on the forums.

https://forums.unrealengine.com/forum.php

Thanks, TJ

Sorry, I just went around it and actually a friend is making a completely new kart (I got this one originally from blenderswap, and added the bones), with maya there are no problems. This issue happened in 4.0 I think? so I guess it must be already working better, or it was a problem created by myself.

I am still battling similar problem. It is related to Blender (and Blender only) and has lot to do with unit setup. With units set to metric everything (bone setup, geometry etc) exports quite well, collision meshes look ok in Physics editor (and work there) BUT in game collisions are 100 times smaller then they should be. I am quite happy to share all info you might need.