"Turned over" locks?

[Lesh18]

Hey guys

American/British locks are set like this



which means the pins go from the upper part down. If I overset a pin, the upper pin will get stuck but the lower pin may fall just freely down (due to gravity) and the lock can open.

However, European locks are rather set like this



meaning the pins run from the lower part up. And here is the problem: If I overset a pin on a European lock, the (in this case) upper pin will fall down (due to gravity) and will block the shear line.

Does it mean picking locks that are set in a European fashion is more difficult? What different strategies should we should when we go about picking the two?

Thanks

[Teddy Picker]

American/British locks...If I overset a pin, the upper pin will get stuck but the lower pin may fall just freely down (due to gravity) and the lock can open.

Think about how the lock works. When you're picking, you're dealing with the binding pin stack. Previously the shear line was binding on the driver, but now that you've overset, it's binding on the pin itself. The binding is going to be enough of a "pinch" to keep the pin in place regardless of which direction gravity is pulling. There might be a chance that if you overset more than one pin, which pin is binding might change, and one of the overset pins might drop to the shear line (become "set") but that is likely going to be due to pressure from the spring, not from gravity. In short, gravity has a pretty negligible effect on the system. Does that make sense?

[Solomon]

Oversetting has nothing to do with gravity. Overset is overset, you can't push a pin too high and have the key pin magically just fall back down. If a pin is pushed too far, the key pin starts to bind and gets stuck. You need to release tension carefully to correct it. Doesn't matter if the pins are up top, on the bottom, or sideways.

The reason pins stay set is because the plug turns a tiny amount when the binding pin stack shears... this creates a tiny ledge on top of the plug which the edge of the driver pin can sit on top of. This ledge is what prevents the spring pressure from firing it straight back down into the plug again. When you find the binding pin and lift it to shear, the key pin will then sit inside the plug not really doing anything. The only difference when the pins are on the bottom, is that the key pin sits at the bottom of the keyway rather than moving up and down freely in its chamber. It makes no odds to picking.

So, if the pins are up top and you lift too high, the key pin binds and gets stuck so you need to release tension to drop it back down. And if the pins are on the bottom and you push too far down, the key pin binds and gets stuck so you need to release tension to let it spring back up.

[boggif]

You can easily try it out yourself: just pick any lock in both ways ie. normally and upside down.

The springs work as usual but there is a one difference: If a pin falls down from the top you can still feel it (and be sure it is not overset) like on an American setup. If the pin sits at the bottom, you cannot feel if it is overset and binding or resting at the shearline.

[Solomon]

If the pin sits at the bottom, you cannot feel if it is overset and binding or resting at the shearline.

Course ya can! Set pins will have a tiny bit of give to them. It's true that binding pins and overset pins will feel pretty much the same, but there is a certain feel to an overset pin. I can't really put it into words, with practice you kinda just know. But if you have a pin that feels like it's binding and it won't set no matter how far you push it, or it causes pins to reset as you push on it, then chances are pretty high that the pin was overset.

[Capt_Tom]

Think about it.... a pin column (with no master pins) has a spring and two pins in the stack. The intention is to set the top pin (spring loaded pin) into the top of the lock above the shear line, while leaving the bottom pin (which rides the key) in the plug/keyway, below the shear line. You cannot overset the top pin. The bottom pin (again, which rides upon the key) is the one that you may overset. When you do, it is HUNG at the shear line.... until you release some tension, at which time it is pushed down by the spring loaded top pins.. and you try to set it again. Gravity has nothing to do with it.

Forget the line of pins in a lock and think about only one stack. Learn what the pins in one stack do. Then move on.