They hold together everything from the most delicate watch to the largest bridge. The world is literally kept from coming apart by screws and bolts, and yet we don’t often give a thought to these ...

Can you make a screw out of a piece of paper and pencil? Your friends might think it is magic, but it’s science at work. Here’s an easy experiment that might add a “twist” to your thinking. MATERIALS ...

The degree to which a ball screw performs well in the field is the direct result of the process used to make it. Grinding, rolling, and whirling are the most common ways to thread ball screws. Some ...

This close-up of the ball contact in a profile projector shows a gothic arch. It consists of at least two radii slightly larger than the ball used, but offset so the raceway touches the ball on both ...