I've been away from these boards a couple years, but I am back. Let me weigh in on an explanation of the
Machine Doubling in the Buffalo series.
From the early 1900s through WWII, many of the primary coining presses at all three mints were the Ferracute knuckle presses. These were almost all of the presses at the Denver and San Francisco mint during the
Buffalo nickel years. Remember that the Denver and San Francisco mints originally were created to strike gold coins, and incidentally the silver coins. They never expected to strike bronze or cupro-nickel coins. The Ferracute presses did an adequate job striking soft metal coins, such as gold or silver. They did a poor job with bronze or cupro-nickel coins.
These coining presses used a knuckle (rocker arm) assembly to roll the hammer die (obverse die for most coins) across the top of the planchet, forcing the metal into the two dies with both pressure and motion. Think about how we walk, with our heels touching and our feet rolling forward until our toes touch. The tonnage of the presses varied from 110 tons to over 250 tons. These presses were slow, clunky, extremely dangerous to operate, vibrated like crazy, and required hand feeding the planchets into a tube, which then dropped a planchet into a feeder and moved the feeder into the striking zone when the knuckle was retracted for the next strike. It was this rocking motion of the hammer die that made
Machine Doubling common throughout the
Buffalo nickel series, especially at the branch mints, both because of the press and because of the hardness of the cupro-nickel composition.
Knuckle presses at full capacity could only produce around 5,000 coins per hour. In comparison, a modern Schuler lateral press can produce 50,000+ coins per hour. A few Ferracute presses were still in use through the 1950s, but almost exclusively were used for silver quarters and half dollars by that time, because of the softer metal, lower relief designs, easier size of planchet for hand-feeding, and much lower tonnage required to strike the coins. They were replaced first by the single-head vertical strike Bliss presses, and then by the more modern four-head vertical strike Bliss presses, both of which were vast improvements for harder metal coins.
The need to hand-feed the presses also explains both the extensive die clashing throughout the Buffalo series, and the need for extensive die polishing to remove evidence of the clashing. The proximity of the feeding tubes to the hand-chomping dies and lack of safety guards on the knuckle presses made them exceptionally dangerous. It also explains why the die polishing was vigorous and done with little care for the dies, especially in the branch mints.
There are videos online of the Ferracute presses in operation. Ferracute knuckle presses (thankfully) were made obsolete by the four-head vertical strike Bliss mechanical presses. The Bliss presses were made obsolete by Germany's Schuler lateral presses. Ferracute went out of business in the 1960s.
If anyone is interested in chasing this issue further, Ferracute's business records are available on microfiche (yes, really) at the Hagley Museum and Library in Wilmington, Delaware. They have the Ferracute order records and design drawings for the US Mint. In may be possible to determine which presses were used for coining the
Buffalo nickels. If anyone wants to live dangerously and doesn't mind losing fingers or hands from these monsters, they can even buy some of the mint's old Ferracute coining presses. They are still in warehouses and listed by machine vendors all over the place. They weigh 5-9 tons each, probably need complete rebuilding, and are among the most dangerous machines ever built. But they are still lurking out there.
Posted 03/04/2025 01:27 am
