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Archive for December, 2010

That Magic Medal-Making Machine!

Medallic Art Company owes its existence to one machine and the inventor of that machine, Victor Janvier. By learning of Janvier’s new invention three years after it was patented in France in 1899, Henri Weil and brother Felix built the business based on that one machine. Henri’s employer, the Deitsch Brothers, ordered him on a vacation trip to Paris to learn how to operate it and bring it back to New York City. That was the first Janvier imported to America.

Janvier Reducing Machine

Janvier Reducing Machine

Victor Janvier was a master craftsman, mechanic, constructeur, and perhaps a sculptor himself. He set out in 1892 to improve upon the existing pour la gravure, pantograph reducing machine, to reduce oversize medallic patterns and cut dies to a desired diameter. He had access to an existing pantograph, perhaps a Hill machine first developed in London 1851, and improved in 1856 and again in 1866 (by the famed Wyon family of engravers in London who had purchased the rights from inventor C.J. Hill).

But the Hill machine had problems. It operated perfectly at first. But as it advanced further into the design, well along the circular path it traced on the pattern, the cutting point began shuddering, it had difficulty cutting into the die.

It was not revolving fast enough. The tracing point was moving over more design and – by means of the connecting bar – transferred that motion to the spindle that controlled the cutter point. With each circular path of their synchronous rotation it increase the amount of relief it needed to cut into the steel die.

Janvier’s experiments led to a brilliant solution. Ideally what was needed was different speeds for the tracing points and the cutting points. What he wanted was for the tracing point to slow down at the same time the cutting point to speed up. His solution was a mechanical one – twin cones pointed in opposite directions with belts connected from the cones to the spindles controlling the speed of both.

Victor Janvier

The speed controlling the rotation of the pattern slowed down. The speed of the cutting point speeded up as it traced the pattern from center point to the outermost design. Over the years of 1892-1899 Janvier built several examples of his proposed mechanism. Voila! It worked. Then he proceeded to improve the total mechanism until everything worked smoothly.  Ultimately he achieved what he was seeking, for the mechanics to work flawlessly, like a Swiss watch! He was granted a French patent in 1899.

What originally was his sculpture atelier, studio – and he did produce some dies for striking medals along the way – became his machine shop for building reducing machines for other sculptors. Just before his death in 1911 he had established a factory for building not only reducing machines, but also enlarging (pointing) machines as well.

His factory marketed these two machines, intended for sculptors, both for reducing the scale of their bas-reliefs, but also for enlarging maquettes, small statues and sculpture in-the-round. But he found an unusual market for his machines – mints for making dies to strike coins. So now Janvier was in the business of making reducing machines. It was not an easy sell at first.

By 1921, however, the reputation of Janvier die-engraving pantographs was widespread and his reducing machines were in 22 countries around the world. The number built and shipped by country are listed below:

Country National
Mints
Private
Firms*
France 33
United States 23
Austria 2 14
Germany 13
England 3 11
Spain 2 6
Italy 2 5
Belgium 1 3
Netherlands 1 3
Japan 1 3
Denmark 2 1
Switzerland 2
Czechoslovakia 2
Mexico 1
Brazil 1
Hungary 1
India 1
Poland 1
Russia 1
Siam 1
Sweden 1
Turkey 1
Total 24 116

*  Some private firms were agents, who, in turn resold reducing machines to national mints, as in the case of United States. Also, once a mint or firm had one reducer, they often ordered more. Not all the machines sold to private firms were used for making coins and medals (as manufact- urers of buttons and silverware obtained more machines than mints, national or private).

But as stated previously this was not a unique invention. It was developed over the years. From my 40-year study of engraving machines I have learned there were 17 individuals and mints that had a part in the development of the die-engraving pantograph, and this occurred in five stages.

The cameo cutter was used by ancient craftsmen. This was powered by an assistant using a bow with the string wrapped around the shaft holding the engraving point, which when dawn back and forth would rotate the shaft. The craftsman had to hold the object in contact with the cutting point.

As pointed out in last week’s Monday Report #32, the Russian Andrey Nartov may have added foot power to a rotating spindle (like an 19th century sewing machine) and given credit for building his turner in 1721, the earliest date in this study. His mechanism was improved in 1750.

First Generation. Completely independent of Nartov, however, a Belgium Hulot (no first name known) in 1766 built a mechanism with a fixed cutter and a rotating pattern that was peddle powered.

Mercklein (no first name known) at the Paris Mint in 1767 built essentially the same mechanism and the first used at a mint.

In 1788 a private Frenchman, Jean Baptiste Barthélemy Dupeyrat built a slightly more advanced mechanism which was widely adapted among French artisans and sold to mints in England (Soho and the Royal Mint) plus the Karlsruhe Mint in Germany.

This ended the first generation of fixed cutter, peddle power machines.

Second Generation. Matthew Boulton, father of the Industrial Revolution, developer of steam power, and builder of the Soho Mint, obtained one of Dupeyrat’s machines and made several copies. His partner and inventor of the steam engine, James Watt, used these in the Soho Mint and upon his retirement in 1804, took one of the Dupeyrat machines and experimented with it, adding improvements until his death in 1819.

Meanwhile at the British Royal Mint they also obtained a Dupeyrat machine the same year 1819.

Again at the Paris Mint Ambrose Wohlgemuth in 1820 improved the Mercklein machine in use there.

Privately in Belgium, Joseph Pierre Braemt in 1824 obtained his countryman Hulot’s machine and made improvements for his own use.

Also in Belgium a sculptor, Benjamin Cheverton in 1824 built his own machine, probably based on a Hulot mechanism.

Thus ended the second generation of fixed cutter peddle power.

Third Generation. This is noted for the rotating cutter in effect making the mechanism a milling machine and the introduction of water power or steam power and the use of belting to transfer that power to individual machines.

In 1824 the British Royal Mint added the rotating cutter to their improved Dupeyrat (obtained in 1819).

Strangely even though the Paris Mint had two different machines on hand, an artist there, Armand Auguste Caqué, about 1830 obtains an old Hulot machine and makes improvements on it.

Privately in France, an individual, Contamin (no first name known) develops in 1836 his most improved machine (possible based on the widely distributed Dupeyrat). The Contamin is what the Philadelphia Mint purchases for use in America also in 1836.

Jean Baptiste Maire in France also obtains a Contamin and improves on it circa 1840.

Then C.J. Hill builds his improved machine based on a Contamin in 1851 and sells the rights to market it to William Wyon for use by the Royal Mint and privately by members of his medallist family. The Hill machine is improved upon in 1856 and 1866. The Philadelphia Mint buys a Hill machine from William Wyon to replace their Contamin.

The British Royal Mint, again, obtains a Hill machine in 1852 and works on it, perhaps combining what it had learned from its previous machines it had overhauled in 1824 and 1852.

In France E. Ledru develops his machine based on a Contamin.

This is the end of the third generation of engraving (a la controlled milling) machines.

Fourth Generation. The age of Janvier’s twin cones and electric power.

In France Victor Janvier begins his experiments in 1892 and creates his innovative twin-cone mechanism. The sheer number of improvements observed in 150 years to bring this mechanism to a perfect functing machine is evidence of the importance of Janvier’s final product.

In effect Janvier produced a machine that every mint in the world needed, as evident by the list above.

After having said the Janvier’s machine was the last word in this long list of improvements, it seems national mints could not accept it as it was. The Paris Mint obtains a Janvier in 1900 and for a 27-year period attempts to improve on it. Likewise the British Royal Mint obtains one in 1905 with similar attempts by their engineers.

Fifth Generation. New names are found on 20th century die-engraving pantographs:  Augenstein, Mintmaster, Keller, Brown & Sharp. Their newly engineered machines provide new features with slight advancements. But the Janvier reigns supreme.

As we enter the 21st century, and computer-controlled die cutting may become the norm, we cannot give enough credit to the Frenchman whose “reducing machine” was the leader of the pack, the pinnacle of perfection, the money making machine for every mint in the world, for more than a century!

At least for the 20th century!


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I have been studying die engraving and engraving machines for forty years. While the first coins were struck from a die made with crude punches in 640 BC, the first “engraving machine” was the use of a rotating drill, the same as used to carve cameos by ancient artisans. It was hand powered by the engraver’s assistant using a bow with a string wrapped around the drill rod he moved back and forth. This caused the drill point to rotate in an alternate direction after each pass of the bow. But this cut into the surface of the die, however slightly, as the engraver forced the iron die against the rotating drill point.
My interest in die engraving machines was heightened in 1966 when I first worked for Medallic Art and spent spare moments standing in front of their three Janvier machines marveling at this amazing mechanism that cut dies automatically from an oversize pattern revolving in synchronous rotation with the diestock.

I was full of questions. But no one could tell me who or when this machine was invented. Everyone knew the name of the machine — Janvier. But who or what was Janvier? Thus I set off on a four-decade search for as much information as I could find on engraving machines.

What I learned was that the Janvier was not “invented.”  It was “developed.” Seventeen individuals and groups had been involved with its prior evolvement. I did learn it was Victor Janvier (1851-1911) who was the person who had created the machine in front of me as I stood in the engraving room of Medallic Art’s New York City plant.

I was able to track the history of this technology back to the mid-18th century and follow its improvements through five stages of development among individuals and technicians working independently and in European mints.

Then exactly one year ago I came across an article on the internet that, in reporting about it, I said it blew my mind. I still hold to that statement today. It pushed back this development of machine engraving by 35 years. I had record of a 1756 event that, if correct, the earliest date should now be 1721. Here is what I wrote:

DID THE RUSSIANS INVENT THE DIE-ENGRAVING PANTOGRAPH?

Russian PantographWhile surfing the internet this week I found an article that blew my mind. It contained illustrations – both photo and drawing – of the Russian “medallion engraver” of 1721. The original machine, created by Andrey Kinstantinovich Nartov, was destroyed by fire in 1747 but drawings and the inventor’s manuscript were uncovered in Saint Petersburg’s National Library that lead a team of mechanics to recreate that original mechanical device 270 years later.

The metal parts of the reconstructed 1993 machine were so precise it worked as well as the original years before. The machine was called the “medallic lathe of Peter the Great,” named after its royal patron, who had established a “turnery” where it was first used. This was a studio where artists created small bas-relief objects carved in bone and other materials on a variety of turning lathes.

That original machine was described in detail by inventor Nartov in his 1755 manuscript, “Teatrum Machinrum,” which could also be another name for the machine. The article also calls the reconstruction a “medallic-copier lathe.” It has also been referred to in print as a “medallion engraver.” With all these names one might expect this contrivance was the earliest “holy grail” sought by hand engravers for centuries – a machine that eliminated the tedium of hand engraving.

Not so. Today we can best describe Nartov’s creation as an elaborate “cameo cutter.”

Cameos have been known since ancient times, originally carved by hand, much like dies were hand engraved. However dies were cut negative to strike positive images, cameos were carved positive, one at a time, without any means or necessity of replication. The first cameo cutting innovation was to power the drill bit with a bow. Imagine a Boy Scout using a bow to start a fire. The bow string wrapped around the drill rotated it as the bow was applied back and forth.

What Nartov may have invented was the foot power applied to his elaborate lathe (like a foot-powered sewing machine of the 19th century). Amazingly the foot power mechanism is missing from both photo or drawing, but the attached article mentions a mysterious “foot gear.” We observe the chuck where the discs to be carved were affixed and the spindle where the cutting point was placed. But we see no provisions for any pantographic reduction.

In Peter’s workshop “turnery” artists cut objects in bone, even from mammoth tusks, as they may have had on hand a considerable supply of these. A few were even cut in metal, as a portrait mold (obviously for casting) is shown in the article. There is no evidence, however, a die was cut in this workshop which could have been used for striking. (Such technology could have cut a die, however; it would be unusual for this to be overlooked.) But without this evidence we must class Nartov’s machine as a cameo cutter. Thus it cannot be classed as a die-engraving machine.

One of Nartov’s machines was in a Paris museum. I had reference to this in my notes (where I learned of this in the Oxford publication A History of Tecmhnology by Singer and others, vol 4). In a study of the die-engraving pantograph, I noted Nartov’s machine was a precursor, along with cameo cutters developed in other countries, notably Britain and France. The first truly engraving machine was the Belgium Hulot of 1766 (documented in Denis Cooper’s Art & Craft of Coinmaking, illustrated page 166). This machine had peddle power and was followed by minor improvements by Frenchmen Mercklein (1767) and Dupeyrat (ca 1788).

The second generation of engraving machines was powered by waterwheels and belting until Mathew Boulton and James Watt added steam power to their engraving machine at the Soho Mint in 1790. The fourth generation was dominated by Victor Janvier who started experimenting in 1892 with his improvements (twin cone drives of the cutting tool and the speed of the rotating pattern and diestock) and patented his miracle machine in 1899. I wrote more extensively on the die-engraving pantograph in The E-Sylum March 14, 2004.

To answer the question posed in the headline: No. Nartov’s machine was not a die engraver, but only a cameo cutter. The invention of the die-engraving pantograph clearly rests with Hulot of Belgium. I wish we knew his full name – he deserves the credit! (Alphée Dubois did an 1875 portrait medal of “M. Hulot;” is this our inventor? Forrer’s Biographical Dictionary, 1:631).

But of all these engraving machines the best was Janvier’s machine. Mints of the world beat a path to his Paris factory to obtain his die-engraving pantograph.

To read the complete article (it’s in English), see: Peter the Great’s ornamental turning lather.

To read the earlier E-Sylum article, see: THE JANVIER DIE-ENGRAVING PANTOGRAPH

This is the first of two posts on Machine Engraving with special attention to the Janvier pantograph. I alluded to the “second generation” of engraving machines in that article above. I will spell out in detail how each step in the development of this machine advanced over previous machines.

Once Victor Janvier patented his machine in 1899 every mint in the world beat a path to his door to acquire one of his marvelous machines. He had created a “money machine.” Literally, every mint in the world wanted his pantographic reducer to cut their dies to strike their coins.

And I will tell you why in the next installment.  Stay tuned.

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