One of this year’s highlights for me was winning the impressioning championships at LockCon. I promise this will be the last posting about this topic, and the only reason to bring it up again is because SSDeV president Steffen Wernéry kept his promise: he edited (and made publicly available) a high quality video about the impressioning games in Sneek.
In this video you can see what it looks like when someone files a key to a lock without knowing what the original key looks like, and create a working key (from scratch) to a lock in minutes. For those who do not know how lock impressioning works here is a quick explanation: a blank key is inserted into the lock, and turning pressure is applied. This turning pressure creates pins to bind into the lock. By wiggling the key up and down when it’s under this turning pressure, the binding pins will make a small scratch into the blank. Once the scratches are identified, a few strokes with a fine file will take away some metal on the key, causing the pins to drop a little deeper into the key. The interesting thing is that pins will stop making marks/scratches when they are at the correct position. The process of twisting and filing is repeated until the pins no longer leave marks (and the lock opens).
Currently two versions of the video are available: one in Quicktime MP4 (230 MB) and one in Windows Media format (320 MB).
Looking back at the video I can only smile. I was under quite some pressure, and I did get a little nervous by the camera at first. Fortunately I could block that feeling quite fast and focus on opening the lock. Hearing me yell ‘open!’ on the video still gets a grin on my face.
I would like to thank Steffen for his hard work of editing the video and make it available in such short time frame. And I can only hope you enjoy the video as much as I do. Hopefully it will get you interested in learning about opening locks this way or give you an idea what impressioning is about and what our games look like ….
You clearly know this, Barry, but a lot of those other guys could stand to be told that files should only be used to cut on the forward stroke. When you press down as the file moves backwards, it doesn’t cut well; and it can dull the file by breaking off the tips of the teeth. (Which in turn can lead to the nasty screeching sounds that the video is filled with — although those can also be due to the file being clogged.)
Yep, the sound comes from pressing the file against the material and pulling it towards yourself…nasty sound :/ Think about a small metal saw: It also cuts only on the forward stroke and when you use it, you ease of the pressure when pulling it back. The same thing should be done on a file 🙂
And congrats Barry, that was very fast opening and I’m sure the Germans are practicing for the next championships as we speak 😉
Norman and Jaakko: Filing back and forth will give the blank a very smooth and homogenous surface that is ideal for spotting marks. I know that from a technical point it all looks and sounds silly, but truth of the matter is that practice shows filing this way will result in getting better marks.
One of the reasons I do not file back and forth (on this video!) is because I use an exceptionally long file. With this file 3/4 of a stroke is already enough to cut one position deeper. And by not going back an forth with this file I saved valuable seconds. Seconds that added up in beating Meister Arthur in little over half a minute …
That’s right!
Filing in both directions is almost twice as fast als only filing one direction. You do not need to lift the file from the blank, you do not need to aim when putting it bank onto it. You can stroke much much faster fore an back.
These coarse files from the hardware store really get blunt filing the wrong direction. An fine impresioning file gets better and better over the time. The first blanks you use it “the wrong way” it gets a very little bit more blunt, but then it leaves a much better surface to spot the marks. Try it!
André Matuschek
Andre, if I’m correct the “bluntness” comes from the file gradually clogging. Does anyone clean their files with a brush every now and then? 🙂
Congrats on your win!!
The file does not clog! It gets a little blunt, no need to clean it. If the file gets clogged, it is really hard to clean it. That happens if you file Wood’s metal keys, for example to remove the sprues.
haahha, you were very excited when it opened. It looked like a real pro and you knew that lock and the pin depth sizes.
The teeth of files tend to be shaped like saw teeth, if you have a good brand of file. They cut much better in the forward direction, and are structurally weak in reverse. I’ve put up a closeup photo of a file, to illustrate:
http://yarchive.net/photos/file_closeup.jpg
Note how each and every tooth of the file is perfectly shaped. The scale might not be apparent from the photo; this is a tiny file, about five millimeters in width and a millimeter and a half thick. Files tend to be regarded as old, low-tech, and simple; but this is precision engineering on display, made by Grobet in Switzerland.
In any case, on reflection, filing in reverse does make some technical sense here. The lesser cutting action that you get filing in reverse would tend to smooth over the deeper cut made by the forward stroke. If you want this, I suppose you should finish with a reverse stroke. If you use mild pressure on the reverse stroke, control the angle carefully so as to keep lots of teeth in contact with the work (minimizing the pressure on any one of them), and are cutting soft brass key blanks, you can likely do this without breaking teeth.
But if you do break teeth, it’s not going to improve the performance of this file. It might help with a file that was poorly made (I’ve seen files that looked like someone made a bunch of parallel scratches in a piece of soft steel, then hardened it), since a poorly-made file has some teeth that protrude much more than others and could stand to get knocked off. But I think it would be better to get a top-quality file in the first place; they’re not expensive. If memory serves, this one cost me six US dollars, several years ago.
Impressive stuff – came across this from hackaday. Good to know that a traditional ‘boot through the door’ is still a quicker entry method though!
Norman – you need to get out more, right?
“Good to know that a traditional ‘boot through the door’ is still a quicker entry method though!”
But with impressioning you would not even know that some has entered the door or has a working key to it. This is why I prefer to say that good lock prevents undetected access through it.
Hi Barry,
First off, congratulations on your win!
Secondly, I would be interested in a few pieces of information: The type of cylinder being impressioned (it looks like an ‘atrium’ style lock cylinder: brand name please), your preferred type of file (Grobet/Swiss#2 8inch for me), and the clamping tool you used for holding the blank.
Now, as mentioned before, a ‘standard’ hardware store file would clog over time, but not the Grobet. Those files are like wine, they just get better with age. Ive been using the same file for some ten years now. The ONLY reason to replace a Grobet file is if it (*gasp*) breaks. Also, the back stroke when filing, in my experience, helps with smoothing the cut so as to make a mark more apt to show.
I too found this page through hackaday.
The type of cylinder being impressioned: Abus C83
http://www.abus.de/de/main.asp?ScreenLang=de&select=0101b06&artikel=4003318309373
The clamping tool should be something like this one:
http://www.multipick-service.cc/htdocs/de/werkzeug/37100/#37185 (see bottom of the page), a vice-grip is not a good idea.
Upload to youtube please
The locks in the video are ABUS C83, Euro profile cylinders as used all over Europe.
Congrats on your win