Medal and coin production is a complicated and time-consuming process and involves many people, from artists and craftsmen through to workers in electroplating and minting. Besides this, multiple machines are used to produce these valuable objects. However, unlike conventional production technology, lasers bring a contemporary approach to production technology and laser engraving solutions, in particular, provide a greater scope for design and contribute significantly toward "leaner" production. FOBA’s GP9000 laser engraving machine (Figure 1) is a light design machine that provides excellent finishing, micro inscriptions, and forgery-proof latent images for security. Precision manufacturing and advanced machines are required to produce perfect medals and coins. To this end, mints employ laser technology in their medal and coin production process because laser-based production processes provide endless design possibilities and potential savings.
Advantages of Laser-based Engraving Process
Laser-based engraving process provides more variety and increased security. Conventional mechanical engraving requires further work processes and hardening times. On the other hand, the laser is capable of engraving directly onto the hardened material. When materials are hardened at the end of the process, the material often gets distorted. However, accuracy can be improved by working directly on the hard material.Surface finishing offers mints a greater scope for design, resulting in new product innovations. For instance, suctures produced through laser engraving systems cannot be achieved with traditional processes. In addition, important security features such as micro inscriptions and micrometer-sized symbols can be produced by lasers cost-effectively and with a high degree of repeat accuracy. Laser-based finishing also saves significant amount of time.
Engraving and Relief Processing Tools and Software
The minting dies and tools used for creating coins and medals are processed manually by engravers. Hence, it is imperative to invest in craftsmanship and technological support. Extensive planning and implementation of a coin or medal project is as time-consuming as it is complex.
Process Steps involved in Laser-based Medal and Coin Production
Using the FOBA medal as an example, a plaster relief (Figure 3) is first created that serves as a model of the artwork to be digitalized during the next stage. Then, the model of the artwork i.e. plaster relief is scanned using a 3D scanner - for the FOBA medal, a Steinbichler COMET L3D. With it, the three-dimentional point cloud is exported as an STL model. Prior to engraving, the live image of the die blank is recorded by the IMP camera system and displayed in FOBA EMC. The scanned 3D data (raw stl. file) is opened in the ArtCAM Pro engraving and relief processing software package, where it is edited and processed directly. Then, the text that appears on the medal is positioned here in the form of 2D vectors, and the 2D graphics designed on the PC for the obverse of the medal are transformed into 3D reliefs. The text, 3D relief data, and enhanced stl. file are then compiled.
Following this, the 3D models earlier compiled into layers with very small layer thickness are split by the software. Through a USB stick, this data can be imported into the FOBA EMC, which serves as the core control software for all engraving applications with FOBA engraving lasers.
About FOBA Laser Marking & Engraving Solutions
FOBA have focused on laser marking and engraving for decades and are experts by experience. Such focus on technology, our consistent focus on challenging applications and complex jobs and one of the broadest product ranges in the market allow us to offer our customers optimal and custom-tailored solutions for their identification applications.From OEM laser markers to laser marking workstations to high-precision laser engraving machines; from standard- to customer-sp ecific solutions: Depending on the requirement, we integrate various laser technologies, add value-adding accessories and options such as vision systems and provide system and machine solutions that are perfectly designed for the marking or engraving job at hand. To Shanghai, Bremen or Ottawa.