Screw Press in Germany?

Insider2

Anyone know if the German States were using a screw presses to strike thalers in the 1850's?

jgenn

I found this in "Screw presses, Boulton presses, and Uhlhorn presses - The 19th century development in Danish coin striking machinery from an international perspective", Michael Märcher.

"The talented inventor and machine builder D. Uhlhorn (1764-1837) had a machine shop (later a machine works) in Grevenbroich, a little northwest of Cologne. In the early 19th century (1817) he developed a new coin striking machine: the knuckle-lever press. The first machine was set up at the mint in Düsseldorf in 1818, where the public saw it. Shortly thereafter, machines were delivered to the mint in Berlin, and the type soon became widespread throughout Europe. After 1820 only a few screw presses were set up at European mints. In the middle of 1863 Uhlhorn’s factory had supplied 146 machines (table 1) for many different mints with Helsinki, Yekaterinburg, Tunis, and Madrid as the probable geographical extremes.

Uhlhorn’s machine was called a knuckle-lever press because it was based on a knuckle-lever mechanism (fig. 6). The machine could exert a significant pressure on the upper die with short, quick, and rotary motions. It was equipped with a flywheel and a crank, and it could be driven by most power sources e.g. hand- or steam-power. The knuckle-lever mechanism revolutionized coin striking.

The mechanism was later used in many coin striking machines, for example at the important companies Heaton & Sons in Birmingham and Luis Schuler in Göppingen near Stuttgart. The machine had automatic feeding and extracting/ejecting, which combined with its successive motion meant that just one person was needed to operate one or several machines if they were powered by, for example, steam. The machine thus required less staff than the screw presses, and it also required less force."

pruebas

I don’t know a thing specifically about the German States, but the larger European mints were using Uhlhorn-derived presses by then. I suspect the smaller mints may have been still using screw presses.

Insider2

Thank You! I'll post the coin's curved radials. I cannot recall ever seeing a coin from all but a few countries using screw presses in the 1850's. Certainly not Germany.

Bob13

Can anyone any offer any insight into why a roller press might be used vs. a screw press? Some of my coins have such a noticeable curve and wondering what the advantage was to this method of production?

Thanks

Insider2

@Bob13 said:
Can anyone any offer any insight into why a roller press might be used vs. a screw press? Some of my coins have such a noticeable curve and wondering what the advantage was to this method of production?

Thanks

I cannot think of any. Screw press is a slower and older technology.

jgenn

A roller press could be hooked up to a waterwheel such as the ones at the "Real Ingenio" or Royal [Coin] Mill in Segovia that was built at the location of an old paper mill on the Eresma River. The Royal Coin Mill began regular production of silver coins in 1586 and introduced the stamping of the year of minting to Spanish coinage. The roller presses of the Royal Coin Mill continued to perform their function until they were replaced by screw presses in 1770.

Insider2

Thanks, for the information on the roller press also!