| Fasteners are the pervasive and unseen force holding | | | | head, a shank, and threads for both guiding the screw |
| our industrial world together. Only gravity can claim a | | | | into place and for keeping it in there. The head can |
| greater responsibility for keeping things together. When | | | | take many forms, including those that allow the screw |
| one speaks of fasteners, one refers to all manner of | | | | to be removed after it has been inserted, and those |
| screws, bolts, anchors, Velcro, threaded bars, and so | | | | that prevent people from removing the screws at all. |
| on. | | | | The lengths, widths, and pitches of the threads all vary. |
| Fasteners hold two or more objects in place, with the | | | | (The pitch is the angle at which the thread is set; low |
| aim of allowing zero movement. A fastener joins two | | | | pitches allow for easier and more gradual insertions, |
| things as one. You might sometimes wonder: why | | | | while high pitches are better suited to metalwork.) |
| don't people just build things as one piece in the first | | | | Most fasteners are made of metal, but there are |
| place? Why use the middleman of fasteners? The | | | | many instances for which plastic screws will do the |
| answer is that not everything is small enough to erect, | | | | trick, or when are just as powerful a material to |
| ship, or otherwise manipulate. Without fasteners, there | | | | replace a metal screw. Plastic fasteners are |
| would be no skyscrapers. There would be no cars. | | | | non-conductive, and, in many cases, heat-resistant. |
| There would be no Velcro tennis shoes or | | | | Whatever kind of fastener you need, there is one out |
| quick-release stage costumes. | | | | there for every kind of job imaginable. Just think: |
| There are many different types of fasteners, made of | | | | humans are tool users, and fasteners are arguably one |
| varying materials. The most recognizable fastener is | | | | of the single most vital tools in history. If there were no |
| the screw. As everyone knows, it is comprised of a | | | | fasteners, you probably wouldn't be alive today. |