Definição

• Blanking Press.  A punch press on which blanks are made. The first blanking press was built in the mind of Leonardo da Vinci, and he recorded this in his notebooks (published 1500). His concept was to have two blanking dies with separate rams mounted back to back so they could blank the same strip. It is doubtful he constructed any part of this machine (but it was built in the 20th century from his notebook drawings; this replica is now in the Smithsonian Institution, Washington).
  The first blanking press we have record of is one built in 1550 by Max Schwab in Augsburg, Germany. He had improved on the screw press and had offered these to the mint in Vienna but was rejected there. Instead the French ambassador in Augsburg learned of Schwab's innovations and ordered all the mint equipment Schwab could produce for the Paris Mint. This included a separate blanking press.
  This equipment was delivered in Paris 31 January 1551 and placed in production. Antoine Brulier is on record of producing coin blanks there in 1552. Elsewhere, screw presses, when not in use for striking coins, were utilized for blanking.
  Matthew Boulton improved on existing blanking presses and was the first to use steam power to operate these at his Soho Mint in 1790. Not only did he create blanks for striking in his own mint, but also he sold custom made blanks to mints around the world (including the fledgling U.S. Mint). Later blanking presses were manufactured by others, including Ralph Heaton & Sons, particularly when they set up entire mints (Marseilles, France, 1856; Mandalay, Burma, 1864).
  With the correct die set – a blanking punch, plate and stripper (see blanking die)  – satisfactory blanking can be done on any kind of press: screw press (1505-1895), knuckle- joint press (1812-date), hydraulic, (1892-date), or even a punch press. Only one blank was cutout with each stroke of these early presses. Single-piece blanking continues even today for short runs (particularly in the medal field).
  With heavier presses, built at the end of the 19th century, multiple blanking
  could be accomplished (dual blanking was done at the Philadelphia Mint as early as 1906). Thus two, sometimes three, blanks could be formed with each stroke of the press, particularly coin blanks under one-inch diameter. This has increased over the years with increased demand for coins. At the end of the 20th century, as many as thirty blanks are formed with each cycle of the blanking press.
  References:                                                                                                                              
  C43 {1966} Gilbert, blanking presses, #25, 27, p 21.
  C66 {1988} Cooper p [early] 97-101; [modern] Chapter 17, 187- 199.

  excerpted with permission from

  An Encyclopedia of Coin and Medal Technology

  For Artists, Makers, Collectors and Curators

  COMPILED AND WRITTEN BY D. WAYNE JOHNSON

  Roger W. Burdette, Editor

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