How a plastic puck becomes a record
The starting piece is a compact measure of PVC—a type of plastic—often called a puck or biscuit. It is warmed until soft enough to flow, then placed between two metal stampers. Each stamper carries the inverse pattern of a record side: raised ridges where the finished disc will have grooves.
Under pressure, the softened plastic spreads outward and takes on those patterns. The grooves are not merely circular tracks. Their tiny wiggles carry the recorded sound; as a turntable needle follows them, it vibrates in response, and the player turns those vibrations into an audio signal.
Why heat and pressure work together
Heat makes PVC pliable, while pressure pushes it into the stamper’s fine detail. The challenge is to fill the pattern evenly across the disc without trapping flaws or leaving the grooves poorly formed. Labels are commonly placed at the center during pressing, where the same pressure fixes them to the record.
Once the plastic has taken shape, it is cooled so it becomes firm enough to hold the grooves, then trimmed around the edge. That transition—from soft, flowing material to a rigid disc—preserves the sound pattern. A record’s audio is therefore built into its surface during manufacture, not added afterward: the needle reads a physical landscape created by heat, pressure, and a precisely patterned metal mold.
