Combination locks! They’re great if you’re skilled at remembering arbitrary strings of numbers, and have a dramatic flair that’s made them a famous part of many a heist movie. They come in a wide variety of styles, and are vulnerable to a different set of attacks than the more typical pin-tumbler locks used on a household basis. If you fancy tinkering with a combination lock, why not 3D print one yourself?
It goes without saying that any lock you 3D print is going to have issues with strength. Such a lock should not be used to protect anything of real value, but it could be handy to prevent the kids getting at the Halloween candy you’re saving for October.
Regardless, 3D printing and assembling your own combination lock is a great way to learn about how they work. It’s a fun project that is also much easier than sourcing and disassembling the real thing. For a greater understanding of the underlying mechanism, this video should make the basic operation clear.
That’s not all 3D printing can offer to the locksport community, of course. You can always print your own keys, too. Video after the break. Continue reading “3D Printing a Combination Lock”
The Ford Securicode, or the keyless-entry keypad available on all models of Ford cars and trucks, first appeared on the 1980 Thunderbird. Even though it’s most commonly seen on the higher-end models, it is available as an option on the Fiesta S — the cheapest car Ford sells in the US — for $95. Doug DeMuro loves it. It’s also a lock, and that means it’s ready to be exploited. Surely, someone can build a robot to crack this lock. Turns out, it’s pretty easy.
The electronics and mechanical part of this build are pretty simple. An acrylic frame holds five solenoids over the keypad, and this acrylic frame attaches to the car with magnets. There’s a second large protoboard attached to this acrylic frame loaded up with an Arduino, character display, and a ULN2003 to drive the resistors. So far, everything you would expect for a ‘robot’ that will unlock a car via its keypad.
The real trick for this build is making this electronic lockpick fast and easy to use. This project was inspired by [Samy Kamkar]’s OpenSesame attack for garage door openers. In this project, [Samy] didn’t brute force a code the hard way by sending one code after another; (crappy) garage door openers only look at the last n digits sent from the remote, and there’s no penalty for sending the wrong code. In this case, it’s possible to use a De Bruijn sequence to vastly reduce the time it takes to brute force every code. Instead of testing tens of thousands of different codes sequentially, this robot only needs to test 3125, something that should only take a few minutes.
Right now the creator of this project is putting the finishing touches on this Ford-cracking robot. There was a slight bug in the code that was solved by treating the De Bruijn sequence as circular, but now it’s only a matter of time before a 1993 Ford Taurus wagon becomes even more worthless.
[rohare] has an interesting teardown for us over on the keypicking lock picking forums. It’s a Masterlock combination lock – specifically the Masterlock 1500eXD – and yes, it’s a completely electronic lock with buttons and LEDs. Think that’s the mark of a terrible lock? You might be surprised.
The first impressions of this lock were surprisingly positive. It was heavy, the shackle doesn’t move at all when you pull on it. Even the buttons and LEDs made sense. Once the back of the lock was drilled open, things got even more impressive. This lock might actually be well-built, with a ‘butterfly’ mechanism resembling a legendary padlock, actuated by a small but sufficient motor. Even the electronics are well-designed, with the programming port blocked by the shackle when it’s closed. [rohare] suspects the electronics aren’t made by Masterlock, but they are installed in a very secure enclosure.
The teardown concludes with a fair assessment that could also be interpreted as a challenge: [rohare] couldn’t find any obvious flaws to be exploited, or a simple way to break the lock. He concludes the most probable way of breaking this lock would be, “knowing some trick of logic that bypasses the codes on the electronics”. That sounds like a good enough challenge for us, and we’re eagerly awaiting the first person to digitally unlock this physical lock.
Most projects we feature are of the metal/wire/wood variety, but there is an entire community devoting to making very interesting and intricate things out of paper. Imgur user [Criand] has been hard at work on his own project made entirely out of paper, a combination lock that can hold a secret message (reddit post).
The motivation for the project was as a present for a significant other, wherein a message is hidden within a cryptex-like device and secured with a combination that is of significance to both of them. This is similar to how a combination bike lock works as well, where a series of tumblers lines up to allow a notched shaft to pass through. The only difference here is that the tiny parts that make up the lock are made out of paper instead of steel.
This project could also be used to gain a greater understanding of lock design and locksport, if you’ve ever been curious as to how this particular type of lock works, although this particular one could easily be defeated by a pair of scissors (but it could easily cover rock). If papercraft is more of your style though, we’ve also seen entire gyroscopes and strandbeests made of paper!
First we start with some protection… for your USB charged devices. Here’s a USB Condom which acts as a pass-through for the power rails but not the data lines. This prevents untrusted charger security exploits. [Thanks Markus]
[OutKastz] seems to think he’s uncovered a price matching conspiracy at Best Buy. His post references an HDTV video wall he has built. But he also discovered that there are two different version of the same television sold as the same SKU. His theory is that this prevents the big box from matching prices on half of their inventory.
When you’re in need of some breadboarding action with your Raspberry Pi and want to make it as painless as possible you need to build your own Pi Cobbler. This is the diy version of an Adafruit product, built using a couple of pin headers, stripboard, and an IDE cable.
Speaking of Adafruit, did you see Ladyada’s teardown of an ICEdot crash sensor?
[Phineas] is showing off a really really small hexacopter. Check out the maiden flight, as well as first indoor and first outdoor tests.
Perhaps this coded entry system will inspire a future project for you. It uses piezo elements to enter a code which unlocks the back door to the company. The glass door already had a series of large dots painted on it. This turns out to be a nice interface for a four button code system.
Many projects use a Raspberry Pi as a web server. But there is more than just one flavor available. [Jeremy Morgan] performed a variety of Pi server benchmarks using Nginx, Monkey, Lighttpd, and Apache. [Thanks Walter]
Can an old TV antenna reflector be used to boost the range of a WiFi dongle? We’re a bit skeptical. Let us know what you think in the comments.
And finally, we do wish there was more information on this upright piano used to play Doom [Thanks Itay].
Here’s a really fascinating circuit that implements a combination lock using relays and logic gates. Even with the schematic and written explanation of how it works we’re still left somewhat in the dark. We’ll either pull out some paper and do it by hand this weekend, or build it chunk by chunk in a simulator like Atanua. Either way, the project sparked our interest enough that we want to get elbow deep into its inner workings.
From the description we know that it uses a combination of CD4017, CD4030, CD4072, and CD4081 chips. You’re probably familiar with the 4017 which is a decade counter popular in a lot of project. The other chips provide XOR, OR, and AND gates respectively. The relays were chosen for two purposes. One of them activates when a correct combination has been entered, effectively serving as the output for the combo lock. The other two are for activating the clock and affecting a reset if the wrong combination is entered.
It makes us wonder if this would be incredibly simple to brute force the combination by listening for sound of the reset relay activating? It’s hard to tell from the video after the break if you can discern a wrong digit from a right once just based on sound.
Continue reading “Combo lock uses relays and logic gates”
[Admiral Aaron Ravensdale], fine craftsman of steampunk wares, just finished up a new project. It’s a sketchbook protected by two layers of security, covered in gilded leather and drenched in the expositions of a [Jules Verne] novel.
The first layer of security for this sketchbook is a combination lock. On the cover are four switches, each with four positions. These are connected to a PICAXE microcontroller which goes to the next stage of the lock once the correct combination is entered.
The book’s security also includes a knock sensor. With a small piezo element hidden under the cover, [Ravensdale] deeds to tap the book with a specific pattern before it opens. The mechanical part is a small hobby servo also mounted to the cover that releases a pair of brass clasps once both locks are opened.
Like all of the [Admiral]’s builds, it’s a fine piece of craftsmanship, equally well suited to take on a holiday with the baron or to the opium dens of Ceylon.
You can check out [Admiral Ravensdale]’s demo of his sketchbook after the break.
Continue reading “A steampunk combination sketchbook”