Modern manufacturing process dies for coinage → see. Links:
http://www.coinnews.net/2013/09/13/how-the-philadelphia-mint-makes-hubs-and-dies-to-produce-coins/
http://www.coinnews.net/2014/01/06/how-the-denver-mint-makes-dies-to-produce-coins/
http://www.mfgnewsweb.com/archives/4/5555/Applying-Technology-feb13/Machining-and-Metalworking-Manufacturing-Its-All-About-Making-Money.aspx
Very instructive series of photographs, thanks for posting !
The sequence of formation of the working stamp during the slow plastic deformation of the tapered portion of the steel billet.
Italian mint in Rome (1950) → see. Video on the link:
http://www.youtube.com/watch?v=G0_UKxSMwxU
Mint in Philadelphia ("about" 1940) → see. Video between 2.54 - 3.30 minutes on the link:
http://www.youtube.com/watch?v=mBjD9N1APsw
Excellent picture collection, Filat. Thank you!
Peter
Must say i very much prefer these examples of old-fashioned craftsmanship over the modern fully-computerized reproduction processes. Thanks for posting !
The process of forming the working part of the stamp for coinage by pressing the tapered portion of the working die steel billet in matrix hub, the Mint in London (1925) → see. Video link:
http://www.youtube.com/watch?v=SKwRj6tYJ0I
Matrix hubs ("positives of") and "working dies" ("the negatives") for the production of of Bolivian of coins of the eighties of the XIX century at the mint in Potosi (Bolivia).
I emphasize:
1. Formation of the working part of the stamp, in the process of slow plastic deformation of the tapered portion of steel billets, occurs once.
2. No repeated die hubbing, offset, doubling of contours of letters, numbers, pictures here and there can not be.
Against what I have said above objections have anyone?