The lack of depth in new US coins

Another, and very important, reason why todays coins are lacking in relief is because of the speed at which they are made. When a coin is struck the metal has to cold flow into the recesses of the die and this takes a certain amount of time. You can get it to flow faster by increasing the pressure but only up to a certain point. back when we had higher relief coins the striking speed was around 60 to 100 coins per minute. There are seven steps to each striking cycle so at 60 coins per minute, one per second, the actual time of the striking and metal flow is .14 seconds. Today the presses are running at 750 coins per minute or 12.5 coins per second. So the actual striking and metal flow time is .011 seconds. Increasing the pressure is not going to make the metal flow 14 times faster (and it is going to break your dies) so the only answer is to make it so the metal doesn't have to flow as far. You reduce the relief of the coins. With todays high speed presses it is impossible to create a higher relief coin. Now the collector type coins are another matter. Production quantities are low enough on those to be struck on the slower presses and still retain a high relief.

 

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Excellent Condor101. I was aware of those points but never put them into proper perspective.

 

Good point Conder

 

Thanks, Mike, for a very useful post.

Not to split hairs, but... with 7 discrete steps, it's true that the seven steps average 0.14 seconds each. It does not follow, however, that any given step is actually 0.14 s. It is possible the "big bang" - the moment of strike - could last less time than that, or more. My guess is less time, as the mechanics of loading and unloading planchets is slower than driving the die - but I could be way wrong on that.

 

Thanks, Christian.

For some reason, we consistently criticize the US alone, even though the critique is equally valid - sometimes more so - for other countries. I think it's closed-minded, often hypocritical, to single out the US. As you stated, that doesn't apply to coins only.

 

True. The associate designer qualifications asked for more than experience with design software alone. Also, the title "associate designer" sounds like a lower entry level position - the bottom rung on the ladder. It would be interesting to see the qualifications for higher level positions.

 

My main complaint with the lack of depth of US Mint coins are with the newer quarters. The frosted bust of Washington has little or no detail. Just my opinion.

Bruce

 

This is just an assumption, but the new laser technology produces a pitted surface as the metal is blasted away instead of being removed with a smooth surface. The irregular blasted surface reflects light totally different than the old technique. This is microscopic but the eye still detects it. The definition in the detail is not as detectable.

 

About 150 - 200 years. While the lettering was punched the early 1793 cents did have the portraits hand engraved into the dies and some of the hair details of the 1794 large cents were hand engraved into the dies. As late as 1800 some of the details for the reverse of the large cents were added to the dies by hand engraving. Many Conder tokens from the 1790's werefrom completely hand engraved dies including the lettering. Some of the cruder CWT's were a combination of punched and hand engraved dies. Hand punching of the lettering died out between 1836 and 1840. Hand punching of the dates disappeared between 1907 and 1909. Hand punching of mintmarks disappeared between 1985 and 1990. And the hand sculpturing of the clay and plaster models has died out in the past five years. Now the designs are created on a computer screen and the computer cuts the master hubs directly.

Every now and then you do still see some hand engraving done. When Ron Landis created his concept designs for the small sized golden dollars in 1999 and 2000 he used a punch to create the profile of Liberty, but the hair, lettering and much of the reverse designs were hand engraved into the dies. But for production coins no, there has been no hand engraving for a long time.