I really love the shelf rail system I have on the wall by the electronics lab; it distributes the load evenly over a large surface, and it’s incredibly easy to move things around and try out different solutions. By squeezing some of the existing shelves a bit closer and moving the wire rolls; I was able to fit yet another shelf 🙂
Stacked Raspberry Pi boards, with common power supply
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I mounted four Raspberry Pi 3’s in an acrylic stack frame, and used a 5V 20A DIN rail mounted power supply to drive them all.