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Complete "How Do They Do It?" Video, Minting Coins

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How Do They Do It? Minting Coins, Season 5, episode 8 March 12, 2008

 

This video may have already been posted here, but the following presentation is the making of a US Presidential Dollar coin

from start to finish, no steps are omitted. (concept to finished coin)

 

 

Linked

 

Minting Coins

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Good video. It has a few small errors but for the most part very good. Most significant error is at 6:52 where they say they are loading the master dies into a stamping press to strike the coins. One they don't use master dies to make coins, and two the die they show is not a finished die. It still needs to be turned down in a lathe to create the neck that will fit into the collar and also create the rim of the coin.

 

Another error is minor. The machine that put the edge inscription on the coin is not an embossing machine.

 

One good thing about this video is that it should show people why the BU rolls you get from the banks or the mint can have a lot of nicks and scratches. From about the seven minute mark on you can see how the coins a dropped, churned, bounced around etc against each other many times. It's a miracle that any of them come out nice.

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Two more thoughts.

 

The use of the plaster model on the reducing machine surprised me. I suspect it was NOT the plaster model. Plaster tends to be too soft to hold up tot the tracing pointer. Years ago they made a metal model by electorplating a negative casting of the plaster model (galvano). Then they switched to using an epoxy casting from the negative of the plaster model. I suspect that was an epoxy model they put in the transfer machine.

 

Secondly this video is three years old. They don't even use the transfer machine now. They also don't make the clay or plaster models. Instead they create the images on the computer as we see them doing in the beginning of the video, and they now use a computer modeling machine to cut the master hub directly from the image modeled in the computer.

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Thanks for those corrections, I caught a few like the master die loading into the coining press and thought the reducing machine had been retired but wasn't sure. I liked the floor covered in "ballistic" bags getting ready to ship and the rack full of blank (prepared) dies waiting for the single squeeze.

 

All in all, it is the most complete video I have ever came across (well under a 47 minute TV special) and is easy to understand.

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