Here's another entry from Dick Johnson's Encyclopedia of Coin and Medal Terminology.
In the broadest sense, any engraving not done by hand,
by any device other than a hand-held burin or graver. All machine engraving must have a pattern or template to control the cutting away of the metal surface which is accomplished by a CUTTING POINT, rotary milling bit, or laser. In contrast, hand die engraving places all control in hands and mind of the human engraver creating modulated relief in varying depth and shapes.
Mechanical minded people have attempted to mechanize the laborious task of engraving by hand for hundreds of years. By and large the French have been the most successful since the later part of the 18th century. However, inventors and mechanics have built mechanical engravers in Belgium, England, Russia, Germany, America and other countries.
By eliminating the tedious chore of hand engraving, the task of preparing dies, specifically, passed from the hand engraver to an artist, sculptor, or model maker to prepare the pattern and a craftsman to operate the machine. The artist is given the credit he or she is due for the design, however, only rarely have some machine engraved objects have been signed by both the artist and the machine operator. (Several medals for the Columbian Exposition of 1892 were signed by both artist and machine operator, for example.)
Despite attempts for over 200 years no one as yet has devised a machine to engrave what a human artist can do. An engraved design or die cannot be created from a concept, drawing, outline, photograph or grid, no matter how hard everyone has tried. An artist is required to create the design, the relief or the pattern. Machine engraving is only a tool to supplement such artistic endeavor, not to replace the human artist. The design must be filtered through the mind and talent of the artist.
Early mechanical die engravers. The first machine engravers were hardly more than cameo cutters or copying lathes at the end of the 18th century. They possessed an arm for reducing a bas-relief design with a cutting point that acted much like a lathe. As the pattern revolved the cutting tool was pressed in as far as the arm controlled by the pattern allowed. Pretty primitive.
Later models had a rotating cutting point which made the engraving machine a mechanically controlled milling machine. Many machinists attempted to further develop such a machine to the end of the 19th century, but the best die-engraving pantograph had been created by Victor Janvier in France and patented in 1899.
Modern pantographs are amazing machines. Not only can they reduce the complete model and cut a die to the required size, they can also vary the height of the relief, enlarge instead or reduce, change the polarity (a right-facing design can be changed to a left-facing design), or it can be programmed to add a die camber (raising the center slightly from the rim inwards).
Then it can start all over again and do the same in any other size within its ratio capabilities. An 8-inch pattern, for example, can be reduced to a 3-inch and 1 1/2-inch dies for medals, and ?-inch die for charms. All made by this amazing engraving machine. It is understandable that every mint in the world possesses such a reducing machine. These included the Janvier – the preeminent engraving machine – but others as well. See pantograph.
Tracer controlled die engraving. Another form of die engraving by machine has been the use of the tracer controlled machine. From a hard line drawing, a cartoon, the operator pantographically reduces and, by a rotating cutter, cuts an outline design as the tracer is guided by hand over the outline of the design. At the operator's option he can also outline the lettering.
The operator – or hand engraver – then routes out the dead metal from the part of the design so intended. At this point he must work the rest of the die by hand, creating he modulated relief for the devices, decorations, lettering and ornamentation. He then sharpens up the lettering and touches up the die as a finely hand worked stage. See Gorton.
Flat engraving and inscribing. For inscribing lettering on any flat surface (either on medals, trophies, nameplate or such) are the common engraving machines seen in jewelry and trophy house workrooms. These operate from template letters (matrixes) that are guided by hand with a stylus in the grooves of the template.
Early models with templates had only one size template for each typeface. These could be reduced, same size or enlarged on the flat engraving machine. A different matrix was required for each alphabet, particularly for foreign languages with different style letters. Sets of symbols were also available.
Computer inscribing. Templates have been completely eliminated by the new technology of computer inscribing, now available on modern engraving machines. Hermes, a firm formerly supplying mechanical engraving machines and templates is now a leading brand of computer engraving systems.
Hand engraving versus machine engraving. Hand engraving is, of course, more expensive than machine engraving and may be thought of as better or more attractive because of this. However, it depends upon the experience and talent of the hand engraver. It is also thought that machine engraving may be more uniform, since it is created from the same pattern letters. This is somewhat true. But here, again, the experience of the engraver – and the time required – are the deciding factors.
Hand engravers also have a wide selection of tools; because of this they can create far more variety in their engraving work. Machine engraving, for the most part, is limited to the router points of their machines. They can vary the shape or width of these, but, again, the end result may appear more mechanical, more uniform.
Finally, hand engraving can engrave in places that machine engraving cannot go; the edge of medals for example. In general, however, the diagnostic evidence for machine engraving is the uniformity of repeated elements, as lettering.
To read the complete entry on the Newman Numismatic Portal, see:
Wayne Homren, Editor
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