‘Unbreakable’ Lorenz SZ42 Encryption Machine to be Resurrected with 3D Printed Motor

March 9, 2017 by Bridget O'Neal 3D Printing

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One of the greatest gifts that 3D printing has brought to the modern world is the conquering of obsolescence. We’ve seen this repeatedly, for auto and jet parts—and more. Now, 3D printing is reviving another encryption device from the 1940s.

Previously, we were fascinated to learn about the Enigma machine used in World War II, brought back to life by students who 3D printed the housing shell for holding the brass contacts and writing, along with several rotors, the compensator, and parts of the keyboard.

Another encryption machine has been found—this time, in Norway, and it is on loan from the Norwegian Armed Forces Museum to the UK where engineers from Her Majesty’s Government Communications Centre (HMGCC) are re-creating a missing motor for the Lorenz SZ42 cipher machine—developed by Nazi forces and known as ‘unbreakable.’

The cipher is being shown at The National Museum of Computing (TNMOC) in Bletchley Park, Milton Keynes. Its history revolves mainly around the WWII era, as it was made by the Nazis and then distributed in 1942. There were 200 such machines made, meant to allow for secure messages to be sent to ground troops. Today, only four are known to be left—and this last cannot function without a working motor.

“The HMGCC team will take three-dimensional images of an existing Lorenz motor and then reconstruct it using 3D printing techniques,” said John Whetter of the National Museum of Computing. “Externally, the motor will be almost indistinguishable from an original.”

The Lorenz SZ42 [Image: The National Museum of Computing (TNMOC)]

Not only is this a great way to educate the public on the wonders of 3D printing and what its technology can do in practically creating obsolete parts out of thin air, but there is also an enormous history lesson to be learned. Once the machine is up and running with its 3D printed motor, the HMGCC staff look forward to showing how Nazi troops used the encryption machine. They will also go into detail about how another machine—the Colossus—proved that it was not ‘unbreakable.’

The Colossus was in fact a reason that the war ended, adding to the defeat of Germany with the help of the British and their in-depth intelligence. This was aided by Bill Tutte, known as a codebreaker, and Tommy Flowers, who created the Colossus. The machine was able to crack code coming from the German troops, as British intelligence agents such as Betty O’Connell and Irene Dixon (below) intercepted crucial messages. Oh to have been in their shoes at that time!

Image: The National Museum of Computing (TNMOC)

The Lorenz SZ42 is also of great historical value because it is known to be the machine which received the final surrender message on May 8, 1945, indicating that the war was over. The newly refurbished machine should be finished by summertime, according to the TNMOC team.

[Source: TCT Magazine]