Lengths of driver pins

[abroxis]

Is it true that some locks have driver pins of varying lengths so that the total length of all the key pin and driver pins are equal?

Seems that most of the locks I have seen have driver pins that are all the same length with only the key pins of different lengths.

[KokomoLock]

Yes it is true, it is called Balanced Pin Stack, normally found on higher quality locks.

[bezza1]

yes it is true i have found several locks with balanced pin stacks

[KokomoLock]

And why do they do that you may ask? I believe it is to prevent any kind of "overlifting attack". If you have a short keypin and a short driver pin it would not be hard to lift the keypin over the shearline into the book. With balanced pin stacks there is not enough room in the book for a compressed spring, driver and key pin so overlifting is not an option.

[LocksmithArmy]

they also do it to prevent an old decoding meathod of simply checking the wheight of each pinstack, if one is lighter than another its a smaller keypin...

and for a specific lock (if you were wanting to check it out) all sfic lock equal 21 when all the stacks are inserted correctly (21 by number of the pin in a pinning kit)
so if you had a keypin of 4 a master pin of 2 and a controll pin of 8 you would have to have a driver of 7 and that stack would be correct

its a good check when pinning these pitas... when done pinning a lock look down the chambers and if a stack is not evenwith the rest you know u messed up

[magician59]

The biggest reason most manufacturers balance the pin stacks is to prevent crushing the springs, when the full width of the key (as in a key blank, or shallow-cut key) is inserted into the plug.

[xeo]

Its also to prevent "comb" picking, where you insert a pick like the one shown below and push the entire pinstack above the shearline.

[LocksmithArmy]

combpicking is overlifting...

[xeo]

combpicking is overlifting...

Not all noobs know this and nobody mentioned comb picks.

[datagram]

There's actually a variety of reasons they do this:

* To prevent overlifting (which is what comb picks do)
* Distribute wear on the springs evenly.
* Prevent static decoding on pin stacks; raising them all to the top and measuring the distance travelled, or measuring the weight of each stack, and so on.

dg

[awol70]

Just to add:you can balance pinstacks by using key pins as drivers. ( an added bonus is you can key 1 cylinder a multitude of differs... so if you had a 36745 pinned lock,driven by 74365 drivers,you could have say, five precut keys, to practice repinning,and picking different bittings.
(slightly off topic but worthy of note.)

[Tarquin]

So if I don't take the time to make sure my pin stacks are even when I rekey my lock, it's not making it any easier or any more difficult to pick? It's not impacting my skill in any way?

I just wanted to ask to see if I should bother rekeying my lock AGAIN so that the stacks are even, but if it's not impacting my skill acquisition then I give nae damn.

[magician59]

Balancing pin stacks will help you with the limited space in cylinders that have screw caps, short bibles, or special function, such as removable or interchangable cores. Otherwise, it isn't necessary and won't adversely affect your picking.