If you're doing some home renovation work or hanging something up, you'll need to know where the studs in your walls are. But you don't need a fancy stud finder device - a magnet will do just fine.
Most screws are magnetic, and screws are commonly used in home construction. So, the studs in your walls probably have some screws in them. In this video, YouTuber Jaime S. shows you how you can find those screws - and thus find the stud - with a cheap magnet. Just move your magnet along the wall until the magnet gets drawn in and connects. Now you roughly know where the stud is, as well as where you shouldn't drill or hammer directly (because there's a screw right there).
Jaime uses a magnetic pick up stick to do this, which is designed to extend and pick up screws or other loose metal building materials, but you can also use a typical rare earth magnet if you already have one of those. The advantage of using the pick up stick, however, is you can extend the stick after placing the magnet on a stud and use it as a plumb bob. Now you can easily find the stud below the magnet as well.
Inexpensive Stud Finder Using a Magnet! [YouTube]
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