Reed Switch

thingiverse

This device utilizes wall hooks conductive and magnetic, affixed to printed parts via hot glue. By leaving a half-inch gap on one end, a magnet near either side bends the metal pieces together, thereby closing an electrical circuit. Although not as sensitive as commercial options, this homemade switch proves functional. For demonstration, refer to this YouTube video: https://www.youtube.com/watch?v=b4piw_LMiRg.