Importing custom collisions not working as it should

If I make changes to my UCX_mesh and import the mesh back in it’s lost some of the collision data on the way.
Used to work just fine with 4.12 but now with 4.13 there’s something wrong with the importing.

Hi Tonzuko,

Can you please provide a test asset that shows this to be the case (preferably a source Max or Maya file) for testing this?

I use custom collision on a regular basis and have not run into this issue and the details provided don’t necessarily indicate how to reproduce your issue specifically.

Thank you!


Hi, thanks for the reply. I’m using blender so I have only the .fbx or the .blend file but here is the fbx. The bottom part and the stairs import fine but then the middle part does not. Dropbox - File Deleted - Simplify your life


Hi Tony,

After looking at your meshes setup collision everything is working as intended based on how it was named.

Currently you have a single UCX_longtail_hut collision primitive. When collision is imported for this, it will only generate a non-convex hull shape. You have to split each section up so that it imports properly. So the floor, the standing wall, and each individual stair need to be named UCX_longtail_hut_XX. In this example you should replace XX with a number from 01 to 06.

Then once you import you should have correctly setup collision shapes. This is all covered in the documentation as well here: FBX Static Mesh Pipeline in Unreal Engine | Unreal Engine 5.1 Documentation

I hope this helps.


Aaah yes, this makes a lot of sense now, thank you very much!