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