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Old 03-26-2008, 01:22 PM
Tom Maringer's Avatar
Tom Maringer Tom Maringer is offline
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Join Date: Mar 2008
Location: Springdale Arkansas
Posts: 48
Default Re: Engraving coining dies

Quote:
Originally Posted by Gail
Tom, It would be interesting to see some of the antique dies and hubs. gailm
Okay Gail. Here is a drawer of handcarved master hubs. This is a very small subset of my collection but hold some that I have actually used to make dies. The hubs are hardened tool steel and are handmade by engravers. Some of them show very small "SP" initials in the flat field. Those are creations by one of the great masters of this genre, Stan Pearson, who worked in the Kansas City area from the 1940s to the 1990s.


This is a closer view, focusing on one particular hub of a miner in turn of the century garb with a pick.


Here is a coining die created by pressing that hub into annealed tool steel, then turning it flat, and adding the lettering using a Gorton pantomill. The "rim" of the coin is created by the lathe-cut at the edge of the die, and the "neck" of the die fits into a collar that forces the rim up when the coin is pressed. It took about 200 tons of force to hob that image, due to the broad area and high relief. The flat fields are polished on the lathe using fine abrasives on flat sticks. (no buffing!)


Here is the obverse side of the bullion coin created using that die... one full troy ounce of pure copper. I did the coin in celebration of the Copper Country of Michigan's Upper Peninsula. It is currently for sale in a number of gift shops around that area. It takes about 150 tons of force to get full strike-up on this coin.


Here's the same coin shown on edge, to show how the collar forms the smooth edge of the coin and helps the rim get pushed up.

Here is an example of a master engraver's work being replicated so that many people can enjoy it. Even if the die breaks (which happens far more often that you might think) it can be re-created by using the archived hub.
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