Hey there @JackieHex! Welcome to the community! So it’s somewhat dependent on how your game works, but some common ways I see building systems handle this is:
- Checking if adjacent to the same type of object and changing to a connective mesh
- Checking if adjacent to a block that occludes that side and just not rendering internals (Minecraft)
- Have each piece offset in a way in which they clip inside of the other object but not 100% flush (Valheim).
Are all of your meshes blocks?