The fifth part for the Computer Lab Box is to build the box itself. The Ikea KNAGGLIG wooden box has the optimal size for four slide-in modules. Every module is an aluminum perforated plate. The size and the distance of the holes on the module are arranged in that way that I can mount all mini-PCs (Raspi., BBB, power-switcher, …) with at least two screws on it. Unfortunately, my local electronics supplier didn’t have enough cables and spacer sleeves for me to finish the inner life of the box. I will finish everything soon.
ad Part 1: I found out that my USB-micro Cable was too thin and too long for the main computer (Raspi 3). I have to find a thicker cable, then I can use the OTB charging adapter for all my modules in the box.