2000 US Mint First Steam Coin Press Medals
The U.S. Mint First Steam Coinage press ran into production problems back in 1836 when it was first put into production and again in 2000 when it was transferred to the ANA from the Franklin Institute.
I'm a big fan of the First Steam Coinage Press and have been lucky enough to have acquired some of these later errors. Here's one that's known as "The Train Wreck" which fused two planchets and pretty much destroyed the first die. An article from Numismatic News describing the situation is below.
Numismatic News wrote:
According to Joe Rust of the Gallery Mint Museum in Eureka Springs, Ark., who according to Baker "put in a Herculean effort working on this press," the problem was a capped top die. A struck planchet stuck on the top die as another blank was fed into the press. The die then came down and struck the two planchets. Simultaneously, the bottom die was moving faster than top die. The jam caused two bolts to detatch.