October 31, 2014 AT 12:00 am

This Pi-based printer makes self-destructing documents straight out of a spy movie #piday #raspberrypi @Raspberry_Pi


Vice sat down with the creator of this self-destructing printer made using Raspberry Pi. Check out the full interview here.

Between Edward Snowden, the Fappening, and the recent Snapchat leaks, it seems clear that it can be extremely difficult to keep information out of determined hands in the information age. Computers are still an easily undermined medium on which to transmit secrets, so in response, artist Diego Trujillo Pisanty has taken an old-school approach to keeping confidential documents safe. On a grant from the Mexican Fund for Culture and Arts, Diego built a printer that prints self-destructing documents. The paper exiting the printer catches fire via a chemical reaction almost immediately, reminiscent of every 70s-era spy movie ever made. The project, called This Tape Will Self Destruct, was debuted outside of Mexico City in late September. I interviewed the device’s creator over Skype at his home in Newcastle, England, to learn more.

VICE: So how does your device work?

Diego Trujillo Pisanty: Well, the document gets printed by a normal thermal printer on receipt paper. Then there’s a series of mechanisms that apply two chemicals, mainly. One of them is a potassium salt, and the other is glycerol, or glycerin—it’s the same thing. When those two come together at the end of the process, they catch fire. The control mechanism is an Arduino connected to a Raspberry Pi computer, and the Raspberry Pi controls the thermal printer and tells the Arduino when to activate specific mechanisms.

How long did it take you to build this?

About a year.

A year?

Yeah. It was funded by the Mexican government as a program to support young artists and to give them money for a year, and then after that they have to present a finished piece, so it was scheduled to take a year.

Did you have to pitch the idea, or was it an open grant?

No, it’s actually quite competitive, and you have to pitch the whole idea. I had to tell them I was going to be burning things in my house with their money. I had to present the political context of the piece, and originally it was going to be a different chemical reaction, but that turned out to be a bit too unstable, and I had to go for something simpler.

Has anything gone wrong?

I had to run it at the exhibition opening; that was part of this program. We did about six demonstrations in about two hours, and on one of the runs the papers didn’t catch fire, so sometimes it fails. Occasionally you need to readjust the mechanism, some things go out of sync, and it’ll start printing gibberish like any normal printer. But with a bit of patience you could get it to run forever, but I think it would be dangerous to run it continuously.

So it’s reloadable.

Oh, yeah. So actually between prints I always reload it to make sure the next print will come out OK. You can change the paper, add more chemicals, and the spray can is actually just a glue to glue the potassium salt in place, so I double-check all that, just like you’d make sure you had ink in your inkjet printer. So the spy equivalent of that.

Check out the full interview here.



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