/diy/ - Do It Yourself

>>1705070
Actually a spiral design like what's inside electrolytics, but with a plastic shaft in the middle that rotates could be a pretty nice design. Though the plate holders/electrodes on either end (the dots in this image) would need to be able to move in and out, probably with a light preload. The shaft itself might need a preload in the opposite direction to stop the thing from unwinding itself. Or you could make the plate holders on a geared mechanism that move in and out in time with the central shaft, but I suspect the springs would be significantly easier. I suspect you'd be able to go from very low capacitances to somewhat high capacitances, depending on your flexible plate material and how well it can bend.