Perforated metal is an important component in many of the structures, items and tools we see and use every day. Because it can serve both a functional and aesthetic purpose, it is commonly used by architects and designers as fencing or guarding around important landmarks.

We see evidence of this in Zurich, Switzerland, where one of our staff captured a series of photos of perforated metal patterns around park house entrances.

He also found stunning examples at the Sechselautenplatz in front of the Zurich Opera house.

This particular perforated metal was most likely laser cut or water jet, however both are similar in that there are holes punched in. Here is how it is manufactured:

1. Perforated sheets come from a mill in large coils that are first fed into a large punch press.
2. As the material passes through the press, tools called punches permeate the steel into a die that creates the holes. Each size comes with a different punch and die set. Similarly, each thickness and material requires their own sets. For example, you can’t take a set for mild steel and use it on stainless steel, and you can’t take tooling for 1/4" holes on 24 ga material and punch 1/4" holes on 16 ga material.
3. The perforated metal is then taken up on coil after it comes out of the press.
4. In most cases, the coil is then fed through flattening rollers to make the sheets flat and then cut into sheets.

Think about this process the next time you see an intricate example of perforated metal, or if you happen to visit the Sechselautenplatz at the Zurich Opera House.