Shells with two layer

Good morning. If I insert two shells inside the “assemble model” command, what exactly happens? I would like to create a shell consisting of two different layers (each with a specific material and thickness), and I was wondering if this step was correct. I attach the file.
file (47.8 KB)

Good morning @fallarinomonica,
the ‘Assemble’-component by default removes duplicate elements. A work-around would be to define the layers at a slight distance and connect them via dummy elements (see attached definition file (62.2 KB) which was done with Karamba3D 2.0.0).
– Clemens