It’s not that the 3D printer I have at home has completely solved our lives, but it has. saved me from buying a lot of products that I could easily replace with a print. And, after hearing about an application capable of scanning old model keys to measure their teeth to the nearest tenth of a millimeter, I wondered: could I use this application to duplicate keys with the printer?
I’m guilty: I didn’t escape printing out all the crap I saw on the internet to see what it would actually look like. From the wolf-shaped keychains (a bit of a weird commission, I know) to a crank motor that’s supposed to work after printing (spoiler: no). As well objects that have been very useful to me: cell phone holders, a broken piece of the Xiaomi fan, bread tools (the best thing I’ve ever printed) or an original keychain for the wall in the shape of owls. And if I keep talking about keys…
I printed some keys after copying them with my mobile. and they work
Print patterns in Ultimaker Cura
My colleague Enrique echoed on Xataka about a curious project in the form of an application (KeyDecoder) which allows get a duplicate of an old key by measuring each tooth one by one from the phone screen. The app itself has no practical application, as it basically serves as a curiosity. However, the measurements it takes are correct and serve to transfer them to a real CAD model.
From this app and a scan I made of the hangar key using Google Pixel 6a and KeyDecoder, I looked for a way to transfer the measurements to the 3D printer. The app does not convert these measurements to a printable model in stl, I had to perform more steps. After the relevant research, I located open source CAD models which allowed me to transfer the measurements into a file suitable for printing. Not only that: I found an automated key generator that directly creates the stl.
I must point out that, despite the fact that the process is completely open and functional, It is not for stealing another person’s keys: the models used are very old, currently there are practically no doors that use these vulnerable models (or they should not, these types of locks do not offer excessive security). In addition, this is a measurement that requires a process of several minutes, it is not enough to take a picture of the key. Even so, I must clarify that copying a key without permission is a crime.
Measure key teeth using the KeyDecoder app
Out of curiosity, I find it impressive what the harmony between the smartphone and a 3D printer can achieve. Because yes, the truth is that a printed key works perfectly: I was able to verify it. After doing several tests and wrestling with the key generator looking for the specific pin pattern, the result satisfied my curiosity: the lock opens. A 3D printed object has much more resistance, hardness and firmness than it seems.
Proof of concept more than satisfactory
Key generator as printable stl model
I don’t think the impression of a key serves to go beyond the anecdote, but it gives an idea of how far technology can go at the closest level, everyday life. I performed various tests, made many adjustments to the print settings, I had to touch up the results with the file to remove the imperfections. After all this work, the lock of the shed opened without difficulty, I found that surprising.
Printing the key on the printer
In my experience, and despite the fact that I don’t think it’s worth buying, a 3D printer can be a good addition to household appliances: with some notions of 3D design, it solves a multitude of problems. A piece of plastic that breaks and for which there is no replacement (or is very expensive), objects that are cheaper to print than to buy (with secondary cost savings, such as transport) or, again, curiosities that favor the use of a 3D printer, such as the Keys project. And I think the next thing will be a Funko with my face: I have to take advantage of applications like Polycam.
