I was a little bit to eager to get the project started so there are no images of the insides of the midsection structure. but its basically four sheets of 1mm plastic hed together by a couple of walls creating a strong boxlike structure.
The more challenging part was the creation of the polygonal surfaces covering the sides of the midsection. The solution was to buld it all in 3d and “unwrap” it to a flat surface like a map. the map was printed and then used to cut out the polygons on .3mm plastic.
but i just had to give it a testrun before cutting it out of plastic. so here is the midsection structure with paper polygons: