We all have a drawer or box full of random hardware. You don’t want to get rid of anything, because once you do, this is the one thing you need. But, honestly, you will be lucky to find what you need there anyway.Enter [Mr. Innovative’s] Nut sorting machineAs you can see in the video below, it will restore order from chaos, at least for the nuts.
You may think that the device requires optical recognition software or some other high-tech mechanism. However, in reality, it is nothing more than a motor with a speed controller. The classification is done by a plastic piece built like a staircase. When the nut is too high to fit in the next step, it will slide out into the output hopper. If you want, you can crank the whole thing without electricity at all.
Drilling out the shaft requires some machine tools, so if you don’t have a lathe, this may not be a good weekend project. Like many commenters mentioned in the video, we may not use the rod holder as a rotating bearing, but for this kind of thing that may run, it may last a considerable amount of time. It would be easy to replace it or even fix the shaft to the motor with a coupler, thus avoiding several problems.
Obviously, the device is not perfect. You did get some errors. We imagine this is a larger nut pushing a smaller nut on the way to the hopper. The Thingiverse file seems to be missing, but in any case, you may adapt to your own design.
It is not that automated, but we have seen a small tool that can help categorize drill bits. Sometimes you also want to sort the small parts by color.