Rivet

A Fastener Formed in Place

The rivet solves a fastening problem that screws and bolts cannot: how to join materials permanently, with a fastener that has a finished head on both sides, when the fastener itself starts as a plain pin. Its construction is minimal — a smooth cylindrical shaft with heads on either end, the heads somewhat larger than the diameter of the hole into which the rivet has been inserted, so the joined layers are trapped between them and cannot pull apart. The making of the joint is the clever part. Generally one head is factory formed, made with the rivet itself. The rivet is inserted through aligned holes in the parts to be joined, and the other head is then formed in place by flattening out the protruding end of the metal. Once that second head exists, the fastener cannot be withdrawn from either direction: there is nothing to unscrew, nothing to loosen with vibration, and no thread to strip. A riveted joint is therefore a commitment — lighter and lower-profile than a bolted joint, and permanent in a way that suits structures and garments alike.

How the second head is formed divides the rivet family. In a solid rivet, force is applied to both sides of the rivet — the tail is hammered or pressed flat while the factory head is held against a support — which requires access to both faces of the work. The blind rivet removes that requirement: a mandrel passing through the rivet is pulled from one side, and its head deforms the far end of the rivet body, forming the second head on the side the worker cannot see or reach, before the mandrel snaps off. Blind riveting makes one-sided assembly possible, inside closed sections and finished structures. Around those two principles the trade has built a catalogue of types: solid rivets, blind rivets, multi-grip rivets, grooved type rivets, peel type blind rivets, plastic rivets, drive rivets, tubular rivets and more, each adjusting the forming method, the grip range or the material to a class of work — heavy structural metal at one extreme, light sheet, plastic and fabric at the other.

From Bridges and Aircraft to the Pockets of Jeans

Riveting's historical scale is monumental. Before welding techniques and bolted joints were developed, metal framed buildings and structures such as the Eiffel Tower and the Sydney Harbour Bridge were generally held together by riveting — hot solid rivets driven through steel members, formed by teams of workers, in their millions. Riveting is still widely used in applications where light weight and high strength are critical, such as in airplanes, where an aluminum skin must be fastened smoothly, without the weight of bolts or the heat effects of welding, and where a failed fastener among thousands does not compromise the whole. The rivet persists because its virtues — permanence, simplicity, low profile, low cost per joint — have never been beaten on all four counts at once by any later fastener.

Its most familiar home, though, is far smaller. Common but more exotic uses of rivets are to reinforce jeans and to produce the distinctive sound of a sizzle cymbal. On jeans, the rivet answers a specific mechanical problem: at the corners of pockets and other points where seams meet and hands pull, stitching alone concentrates strain on a few threads, and the fabric tears away from the seam. A small metal rivet driven through the layers at exactly that point spreads the strain across the fastener's two heads, pinning the layers together in metal rather than thread. The copper-colored rivets at the pockets of a pair of jeans are therefore not decoration that happens to be strong — they are structural fasteners, the same engineering idea that held bridges together, scaled down to a fingernail and put to work on denim. Even the sizzle cymbal makes the same point from another direction: its loose rivets, set in holes around the cymbal's edge, vibrate and buzz against the metal to sustain the sound. One fastener, defined by a shaft and two heads, runs from airframes to work clothes — and in the apparel dictionary it earns its place at the pocket corner, where it has quietly been preventing torn jeans for as long as jeans have had pockets worth reinforcing. On a garment, the rivet also has to survive a life its structural cousins never face: repeated washing, flexing with the wearer's movement, and contact with skin, so jeans rivets are small, smooth-headed and made in metals and finishes that resist corrosion and discoloration of the surrounding cloth. Their placement is part of a garment's pattern, positioned where stress concentrates — pocket corners, and similar junctions where several seams and layers meet — and set through all the layers at once so the fastener carries the load the stitching cannot. A missing or pulled-through rivet is one of the classic failure points of an old pair of jeans, and replacing one requires a proper setter that forms the second head evenly; a rivet set crooked concentrates strain instead of spreading it. That a five-millimeter piece of metal can decide whether a hard-worn garment lasts years or tears in its first season is the rivet's whole argument: the smallest fastener in the garment is placed exactly where the garment is most likely to fail.