Phantom picking

[raimundo]

Once I lived in an apartment where I started to notice a few times when I came home that the lock was in a picked state, the plug a few degrees off top dead center. I thought that someone had picked it until I looked at the key, this key was bitted with short pins near the front and progressively longer pins to the tip of the key. The key was old and not an original copy so it didn't have those 'egg tooth' notches that are what bump keys are all about. The lock was always picked to ccw or the position for locking, apparently as I turned away from the door and pulled the key out, it was turning the plug and leaving it in an unlocked state.
More recently I have noticed the side door to the building where I live had its plug turned toward the open position, and I began to wonder who was picking it. this key is not as stepped down as that apartment key mentioned above, there are some middle deep pins near the bow. I found it in the picked state several times, and suspected someone was picking it at night, but a few days ago, I was in the yard, and knew that I was the last person to key the door and still I found it in this condition. I have never worked on this lock, its the landlords, an Ace Hardware brand. Its hard to explain how it could do this and still allow you to take the key out, unless there are master pins in there adding shear lines to allow it.

Has anyone else seen this? I call it phantom picking. It could be an interesting discussion if others have their stories.

[jpb06080]

Perhaps the plug is severely worn. That, in conjunction with very short bottom pins might allow you to remove the key while its still in the unlocked position. Thats just a guess though. This seems really strange to me.

[raimundo]

yes it is strange, particularily as there is a middle deep cut near the bow, that could only happen if this position has a master pin or if somehow pulling the key out causes something like and overlifting or jiggler effect, perhaps the high tip on the key being the last thing to come out, the pins rise over it and if there is a loose plug tolerance (likely on this lock) the pins just set as they ride down or fall off the tip of the key. like a marshal key or something.
I don't see a lot of discussion of this, arent members running into it? Really its only the second time Ive seen it and the key was the explanation for the first one.

[azza]

It appears that the cylinder housing and the barrel are worn uot. Also the use of master pins to allow for different keys to operate thses doors, a maison keying system, seems to be the culprit. A new cylinder really should be put into the doors.

Also this can happen in the key has high cuts at the shoulder and then progress into deep cuts at the tip. A bad idea for security.

Az

[Schuyler]

Yeah, I've re-keyed / replaced a few cylinders for friends when their locks were no longer key-retaining.

[elipriest]

It may not specifically be wear. If the barrel has been sheared to allow very worn keys to work, the pins can sit below the normal shear line. If the key was pulled in this scenario while the barrel is turned, the pins could move up and over the apex of the cuts.

[Archive555]

My key has done that a few times, especially when I'm in a hurry and pull the key out quickly, and yes, the bumps are progressively larger towards the tip. I might try file a copy down at a slant like that this arvo and see if it does the same thing. Strange.

[raimundo]

I saw it in the picked position again yesterday, I haven't taken it apart, but one thing that I think may also be going on is that hardware store rekey habit they have around here of filing a flat top on the plug to make the shearline wide open. I don't know how often you see this where you are, but its really common around here. its bad practice, it means someone can't find the right length pins so they just cheapen the already cheap locks.

[unjust]

i actually had that happen a few times at my old flat.

the lock later got replaced (by me for landlord) and i got the old hardware. there were a few things going on that seemed to contribute to it.

there was wear to the pins that had left them rounded off on the top and bottom of the bottom pin, and the bottom of the top pin. the appeared to be due to grit.

there was wear to the plug to the point that it could shift inline with the core by almost a cut depth.

the keys had worn down so that the peaks between pins were almost smooth, so that inserting and removing the key wasn't a rollercoaster of peaks and flats, but more of a smooth curve.

the lock was pinned reasonably closely.

so, what was happening as best i can tell is that the tolerances of the lock had slipped enough that it was very easy to pull the key out with the lock partially open, and/or that when removing the key, because of slop in the lock, pins might bind as if it was picked instead of resetting, and then spring force and/or gravity would be enough let the plug rotate slightly