Posts Tagged ‘abloy impressioning’

Abloy classic and trying the ‘reduced contact area blank’

Monday, June 22nd, 2009

In a couple of weeks Han and I will be giving a two day impressioning course in Spain. It is going to be the second course we organize for the Spanish APECS locksmith organisation in nine months. Last time we gave a very successful course on bumping Spanish locks (a small test proved around 80% of the pin tumbler locks on the Spanish market could be bumped). This time the topic will be impressioning.

successful impressioned key for 6 disc abloy camlock

One of the things I am focusing on lately is ‘advanced impressioning’. This means trying the technique on other locks then the standard pin tumbler locks, or modifying keyblanks to make life more easy or have a higher success range on high security locks.

The lock high on my wish list is the Abloy classic (PDF). As far as I know it is the oldest system that uses discs instead of pins, yet it still is (to me) a remarkably secure lock as it has a very high degree of pick resistance. Of course I had to try if I could use impressioning to open it.

My first attempt was to simply give it a try and see what happens. In this case I just took a classic key, smoothened it and filed down where I saw marks. I soon realized this was not going to work. I had absolutely no idea of the exact position of the discs on the blank and the marks kept wandering from left to right. So my second try was using a marker making some dots on the blank, indexing where the discs should be. Still this did not work well as the marks were sometimes appearing between the dots … and I ran out of blanks too …

I recently bought more blanks and could continued the challenge. My new strategy: reducing the contact area of the key. Using a caliper I noticed the spacing on Abloy classic is two millimeters (at least on the locks I was experimenting with). So I marked the blank and removed the material between the positions. For removing the material I used a fine metal saw, a dremel tool (with a diamond disc) and a very fine ‘blade file’ (knive file?). After some work I ended up with a ‘reduced contact area blank’ that looks like a comb.

abloy classic key modified for impressioning (reduced contact area)

Filing down the remaining teeth of the comb is done with a special file. This file is cut only on the thin side. Using this file will only remove material from the contact area of the file, and not from the side of the blade (like on a normal ‘full contact’ file).

I did not have a whole lot of abloy classic locks and was happy to have one padlock I did not know the key-combination of. I did have the key, but put it in a bag without looking at it. Using the reduced contact area key I got the idea I was on the right track … when the key broke off in the lock (grrr). And I could not get the remaining key out of the lock and was out of test locks….

It is a good thing Han managed to remove the key from the lock, and even though I was on the right track I was too deep on some positions.

Talking with Han, we came to the conclusion to start easy using a simple six disc camlock. As most abloy classic locks have a cut 1 (no material removed) on the first and last disc, there were only four discs to work on. And each of these discs could have a cut between one to six (as you can see on this ‘stairway’ key that is cut 1-2-3-4-5-6). This four disc lock did not provide a challenge and was opened in a couple of minutes (without knowing the code).

After this success I did buy some new nine disc padlocks, yet I still have not managed to open them. Somehow I am doing something wrong … so I would be grateful if people would share their experiences on impressioning disc (and lever?) locks in the comments or using a private message …

Of course I will keep trying and report back if I know what is needed to successfully open the nine disc version …

* Update 22/06 21:00: hyperfocus kicked in and … voila … just opened the nine disc version …
All I did was make the teeth of the key a little more thin, and filed in small steps. I must say I am pretty pleased with this success as I have not found any other info out there on people successfully opening Abloy classic locks this way …

successful impressioning on nine disc Abloy classic lock