[Help] Separating Unions appears to be broken

Hey, is anyone else having problems with unions recently? I’m trying to separate a Tree Union into its individual parts, except it turns into a red brick instead. I’ve tried separating other unions and they all seem to have this problem.

Here’s an example for a tree union:

Here’s the model:
tree.rbxm (25.0 KB)

Does anyone have a solution to fix this?


I for one have not had this problem, but when I use the tree you linked it does turn into that same red brick, is the tree a mesh?

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This model has CSG Union in it’s title so it could be the way it was created that is causing the problem

This model also turns into a red brick after being separated.

Alright thanks. Is there any way to recover a CSG union’s original framework?


I’m not entirely sure what CSG Unions are or how they work, but I doubt there is currently a way to get the models original parts at the moment. It’s probably a bug but there’s always the chance it’s something to do with the model it self


If you need to edit the tree you could always export the mesh into a program such as blender, edit it and then import it back with the changes


I actually have the exact same problem with a very common free model. Search up “FAST Helmet” on the toolbox and look for one that isn’t a meshpart. If you look inside the model and grab the base helmet, (“Shell”) it’s a weird union that doesn’t make sense. When you separate it becomes a red brick, just like your problem. What’s weirder is that I don’t think it was even originally a union. It has invisible sections of it just like a mesh. My main problem here is that I’m actually trying to separate it to understand how solid modelling tactical helmets are made.
Here’s a model of the union.