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Electro-mechanical engraving

The basis for electro-mechanical engraving is a copper-coated steelbase with a 0.1 mm strong layer of gravure copper and special surface processing. The so-called cells are engraved in this surface with a diamond stylus. Depending on how fast the cylinder turns around its own axis, the cells are formed longer or more compactly. The diamond stylus is guided via an engraving system, which moves on a slide in parallel to the cylinder axis. To control the diamond stylus, the digital repro data is converted into electrical impulses. The darker the grey values, the deeper the insertion. Up to 12,000 cells can be engraved per second. After the gravure, the cylinder is chromed to achieve better durability. Practically endless identical printing results can be achieved. 

Cylinder design for electro-mechanical engraving
1 Steelbase 30 mm, 2 Chrome 7 µ, 3 Copper 0,3 mm
Standard screen
Cell form: half-autotypical (variable depth and cell opening)
Fine screen
Cell form: half-autotypical (variable depth and cell opening)
Screen angle
left: Standard screen, right: Fine screen                                                                                       left: Engraved letter (standard screen)
                                                                                                                                                               right: Engraved letter (fine screen)
Different stylus' angles
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