Union collision error

I’m attempting to make a simple doorway in a hollow cylinder (which is a union) by negating a rectangular prism and unioning it with the cylinder. This is the result in game:

(note - the doors themselves are basic parts)
As you can see, the player gets stuck in the doorway. I checked out the collision geometry, and this is what im seeing (this is from the outside).

That dark face is where there should be a hole, but it looks like it just kept the original collision geometry instead of changing it.

I’ve tried unioning and re-unioning in several different ways but I can’t seem to change anything. Does anyone know some sort of workaround? My only other alternative seems to be to remake the cylinder as a mesh and do the doorway in blender, but I’d rather avoid that since the proportions would be hell to do.


I don’t know why but this has been happening to me too, it would be best if you just didn’t use unions for the doorway.


It’s because of collision geometry of unions being wonky (which typically happens with larger unions even more so.) For a doorway I’d keep away from doing unions for this reason.

You may need to build a fake walls/floors to solve the issue.

You’ll need to see the physics of the block.

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Yeah I ended up just redoing the thing completely and making it out of parts. The second picture I embedded was a screenshot of the decomp geometry btw

Oh, just looked like the design of the building. lol

I agree with @StandardDoor just do not use unions for the doorway.

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