Beads are regular depressions and notches in the sheet metal. They may look pretty, but their main advantage is that they increase the stability of the metal. Take the grooves around a tin can, for example. But beads are especially important on larger surfaces – think of the channels incorporated into the drainer on your kitchen sink. They're simply beads. They're practical, because the water drains away nicely. But above all, they add to the stability of the surface.
These days, of course, those indentations in the sheet metal are made by machine. But every apprentice metal roofer still learns to bead by hand. And that's a good thing ... and not at all complicated.
Have you seen the creasing stake embedded into the front of the table? On its surface, you can see a range of different slots – depending on how large you want the bead to be.
Slowly and with a steady hand, the sheet metal is guided through the slot and worked with a hammer from above. Any unevenness has to be planished, and then on to the next step ... until the bead is as deep as you want it to be.
A great deal of skill and care is required if the bead is not to be a depression but a raised area. And there's a correct tool for that as well: a hammer that fits precisely on the raised area of the creasing stake. However – if one hammer blow misses, it can easily ruin the whole piece.
Nevertheless: experienced sheet metalworkers can practically hammer out such beads in their sleep!
All depictions: © Europäisches Klempner- und Kupferschmiedemuseum, Foto: Klaus Hofmann
