Die cutting for gaskets, shims and components.

A cutting die is a blade formed to the outline of your part and set in a rigid base. In the press the die is driven through the material against a flat cutting plate, so the outer edge, the bolt holes and any slots are cut in a single stroke and always sit in the same place relative to each other. Ejection rubber packed around the blade pushes the part and the waste free as the press opens.

Because the shape is held in the tool, every part matches the first, and output is fast. That makes die cutting the usual choice for production runs in rubber, cork, fibre, foam, PTFE, films and papers. The trade-off is the tool: it must be made before the first part, at a cost in time and money that a tool-less method avoids. For prototypes and short runs, laser and water jet cutting often make more sense, and the same drawing can move to a die once the design is settled.

Die cutting has limits worth knowing at the design stage. The blade compresses soft material as it enters, so thick rubber and foam can come out with a slightly concave edge. Brittle plastics such as acetal can crack above about 1.5 mm. Very small holes and sharp inside corners need a punch or a radius. Our gasket material chart helps you settle the material before the cutting method.

A rotary die cutter replaces the flat die with a cylinder. Material runs from the roll between the die cylinder and a hardened anvil roll, and parts are cut continuously as the web moves, at speeds a flatbed press cannot match. Several lanes of parts can run across the web at once, and the same line can laminate an adhesive, cut and strip the waste in one pass.

Rotary tools are either solid cylinders with the cutting edges machined in, which last for millions of parts, or thin flexible plates wrapped on a magnetic cylinder, which cost less and suit shorter runs. Both typically hold tighter tolerances than flatbed tools, and they cut thin films, foils, adhesives, papers and foams best.

The limits are part size, set by the web width and the cylinder's circumference, and thickness: rotary cutting suits materials up to a few millimetres. It pays when volumes run into tens of thousands, as they do for automotive and electronics assemblies. Rotary lines also kiss cut self-adhesive parts, leaving them in place on a liner.