Screw threads are another simple machine, and can be thought of as a long, gently sloped inclined plane wrapped around a cylinder. Cut a long right triangle out of paper, wrap it around a pencil ...

The Archimedes screw, an ancient Greek invention for lifting water. Learn about its origins, how it works, and its modern ...

However, as the guys demonstrate, you can create threads by hand using simple methods ... and the machine ran back and forth enough times to create a very nice-looking screw thread.