>Arduino shields The Achilles heel of a bunch of PCB alternatives (conductive ink, conductive plastics, plastic laminates like zebra connectors) is resistance,

>Arduino shields The Achilles heel of a bunch of PCB alternatives (conductive ink, conductive plastics, plastic laminates like zebra connectors) is resistance, which will be hundreds of times worse than copper. Fine for reflective LCDs or capacitive keypads, bad for anything that uses more power. For the carbon connectors in the Fujipoly catalog https://www.fujipoly.com/usa/assets/files/Fujipoly%202015%20Zebra%20Catalog%20for%20web.pdf#page=8 https://www.fujipoly.com/usa/assets/files/Fujipoly%202015%20... they list a current rating for a 0.040"x0.040" pad as 0.005 amps. That's 3.125 amps per square inch. A single 0.10" header pin can do something like 4 amps, and you can fit a hundred of them in a square inch. Non-ideal for shield stacks that want to move current between layers, not just data, like wifi shields or battery shields. (Really high current devices like relay shields or bigger motor controller shields often have their own dedicated power connectors) The gold and silver connectors have better current capacities, but my psychic powers tell me they cost a lot more.