Characteristics of a pin on the verge of setting?

[ooops]

One of my biggest problems is knowing whether I've set a pin. I have a suspicion (paranoia?) that when I'm trying to set a pin (plain cylinder), the stack somehow makes it almost to the shear line but then the tips of the pins somehow bind cockeyed between the shell and plug or some other such weirdness occurs, such that if I want it to completely set, I'll have to use more lifting force than I'd been using at the beginning part of the push. In other words, I can't just provide uniform, gentle upward force (or slightly (negligibly) increasing force to overcome the spring's increasing force besides the uniform binding force) on the binding pin until I feel a tick and feel the plug rotate slightly.

So my question is: am I thinking completely unrealistically? If I've got exactly one stack binding, and I know it's plain cylinder pins, can I check the force needed to begin lifting the stack and know for sure that I can continue applying just this force, nothing more, until the pin successfully sets, or might I have to apply additional force near the end?

[lockjaw]

One of my biggest problems is knowing whether I've set a pin. I have a suspicion (paranoia?) that when I'm trying to set a pin (plain cylinder), the stack somehow makes it almost to the shear line but then the tips of the pins somehow bind cockeyed between the shell and plug or some other such weirdness occurs, such that if I want it to completely set, I'll have to use more lifting force than I'd been using at the beginning part of the push. In other words, I can't just provide uniform, gentle upward force (or slightly (negligibly) increasing force to overcome the spring's increasing force besides the uniform binding force) on the binding pin until I feel a tick and feel the plug rotate slightly.

So my question is: am I thinking completely unrealistically? If I've got exactly one stack binding, and I know it's plain cylinder pins, can I check the force needed to begin lifting the stack and know for sure that I can continue applying just this force, nothing more, until the pin successfully sets, or might I have to apply additional force near the end?

I'm not certain I fully understand your problem so forgive me if I'm off target.

The key (bottom) pin that is paired with a set driver (top) pin has no tension. If the cylinder is conventionally positioned the key pin will fall under the force of gravity because it is no longer in contact with the driver (top) pin which is in turn being pushed by that stacks spring. When you probe a set pin it gives no resistance to your push.

If you have difficulty discerning a tensionless pin from one that is being pushed by the driver (top) pin then you may be pushing too hard or your pick is too large for the keyway. Use a small hook and slowly and gently push through the key way. The set stacks bottom pins will offer no resistance. A set stack feels almost identical to a pin in barrel that is removed from a cylinder.

[melvin2001]

ooops first off, fill out your profile so we know approximatly where in the world you are located. locks differ from one part of the world to the next.

as for your question, what i think you mean to ask is "as i press up on a binding pin, should it require more pressure to lift the further it is lifted." i suppose the simple answer is no. not that you will notice at least. although the feel of a lock is greatly affected by the amount of wear and tear it has faced in its lifetime. every time a key is inserted into a 5 pin lock, the front pin is lifted 5 times (one for each peak on the key), and the back pin is only lifted once. this eventually wears down the front spring more then the rear. also any dirt or other crap that is in the lock will totally change it...

the best way to figure out if a pin is binding is this: Practice. go through digital_blue's exercises and get a variety of locks to practice on. after awile you will just learn what a binding pin should feel like. picking is greatly effected by 2 things.... the type and condition of the lock, and the picking style of the person...

[melvin2001]

crap i ment to say "please fill out your profile"... dont mean to be rude....

[ooops]

I'm in the U.S, and playing with ordinary cheap pin tumbler locks.

I guess I didn't pose my question clearly, so I'll retry:

Suppose I've removed all but one pin stack in my lock.

Now I find the correct torque to use with the following method:
I lift the stack with a pick, then apply a little torque, release upward force on the pick, and see whether I feel the spring pushing the pick down. If so, then I've not applied enough torque, so I try again with slightly more torque. When the pin binds, I know I'm applying the correct torque.

Now: with the stack all the way down, I apply the correct torque, and then lift the stack by applying enough force to overcome the binding force. I continue applying essentially constant force as the stack goes up.
In theory, this should continue until the bottom of the driver pin reaches the outside surface of the plug, at which point the plug should turn (and the lock should open, because I have only one pin stack installed).

However, the pins are slightly smaller in diameter than the holes. This means that the less the driver protrudes into the hole in the plug, the more it's able to twist sideways in that hole due to the torque being applied. Right before the driver pops completely out of the hole in the plug, this twisting is at its maximum (though still very slight).

My concern is that this twisting, or some phenomenon related to it, will result in possibly a substantial, or an abrupt (or possibly both) increase in the upward force needed to shove the pin that last little bit so that it completely pops out of the hole in the plug.
If that's true, then the result would be that I might push up on the stack with constant force, and then feel a very slight rotation of the plug as the driver makes it right to the top of the hole in the plug and twists sideways but doesn't quite pop out, while simultaneously feeling the stack stop moving upward because the force I've been applying is no longer sufficient. The problem is that this is exactly the signal that a pin has successfully set: the plug rotates very slightly, and the pin stack stops moving up. So when I think I've felt a pin set, possibly what I've really felt is just this false signal. If so, the solution to the problem is to shove the pin up harder, and I'll feel it pop out of the hole and feel the plug rotate more than before (but still only slightly if there are other unset pins in the lock). However, if I just _think_ that I've encountered this problem when in fact the pin has successfully set, then applying my "solution" will actually overset the pin.

But if the phenomenon which I'm describing doesn't actually exist, or is negligible, then I can ignore all this and know that in fact, a constant upward force on the pin will result in it successfully setting, and if the pin stops moving upward and I feel the plug rotate slightly, I can be sure that I've really set the pin and haven't encountered the problem described above.

So my question is: do I suffer from excessive paranoia or an overactive imagination, or is the problem described above actually a real problem?

[UWSDWF]

So my question is: do I suffer from excessive paranoia or an overactive imagination, or is the problem described above actually a real problem?

Yes, to all of the above......

and sounds like you're being too heavy handed with both your picking and you tension...

try to relax the pins aren't trying to kill you

[ooops]

UWSDWF: "Yes, to all of the above" ??
Meaning that I'm being excessively paranoid, _and_ the problem described is a real problem?
I don't understand what you mean.

Generally, should I expect to have to apply increased lifting force due to the problem I described, or not?

[lockjaw]

Suppose I've removed all but one pin stack in my lock.

Now I find the correct torque to use with the following method:
I lift the stack with a pick, then apply a little torque, release upward force on the pick, and see whether I feel the spring pushing the pick down. If so, then I've not applied enough torque, so I try again with slightly more torque. When the pin binds, I know I'm applying the correct torque.

I'm not sure whether you are just experimenting or practising at developing your picking technique. I don't think the above procedure you've outlined is a good method of getting a "feel" for the lock. Remember, the logic of single pin picking is to hang the driver pins on the shear line. The "correct torque" is that which reveals the binding pin, allows the driver pin to be set at the shear line and that maintains set pins in their set state.

It's the tension wrench that enables you to get the feedback that tells you that you have set pin. The correct amount of tension will cause the driver pin to pop or click when it is set and will cause the barrel/plug to rotate slightly.

The method you described above will not allow you to differentiate between a set driver pin and a trapped driver pin. Excessive tension can cause you to push the driver pin insufficiently to effect a set yet the key pin will lose its tension because you have trapped it in the shear line.

Now: with the stack all the way down, I apply the correct torque, and then lift the stack by applying enough force to overcome the binding force. I continue applying essentially constant force as the stack goes up.
In theory, this should continue until the bottom of the driver pin reaches the outside surface of the plug, at which point the plug should turn (and the lock should open, because I have only one pin stack installed).

With one pin you will get an instantaneous opening and you should also get a distinct pop or click as the driver pin slips above the plug and hangs on the shear line. You will not necessaily hear the pop but you should feel it in your tension wrench.

However, the pins are slightly smaller in diameter than the holes. This means that the less the driver protrudes into the hole in the plug, the more it's able to twist sideways in that hole due to the torque being applied. Right before the driver pops completely out of the hole in the plug, this twisting is at its maximum (though still very slight).

True, especially with locks that are manufactured to wide tolerances but that should make the settting more evident.

My concern is that this twisting, or some phenomenon related to it, will result in possibly a substantial, or an abrupt (or possibly both) increase in the upward force needed to shove the pin that last little bit so that it completely pops out of the hole in the plug.

The pressure required to set the pin is proportional to the torque you are producing with your tension wrench. The (unintended) pin rotation won't be to such an extent -- even in the cheapest of locks -- that you have to "straighten it out". If applying torque to the plug/barrel cause it to rotate then there must be some rotation of the driver pins (else the barrel wouldn't turn). Certainly, some of the more expensive locks have little "give" in their barrels/plugs (because of the better fit of the barrel/plug to the housing and the pins to their holes) but this doesn't create the need for a special pin lifting procedure. The amount of tension will need to be adjusted and consequently the amount of pressure required to lift the pin but otherwise the general algorithm holds true.

If that's true, then the result would be that I might push up on the stack with constant force, and then feel a very slight rotation of the plug as the driver makes it right to the top of the hole in the plug and twists sideways but doesn't quite pop out, while simultaneously feeling the stack stop moving upward because the force I've been applying is no longer sufficient.

Security pins (spool, mushroom and serrated) rely on this false setting and pin rotation to deceive the lock picker. I can't imagine this happening with regular pins unless you vary your tension (increasing as pin in pushed) such that you trap the driver. If it's a regular pin and your tension is constant then it will be able to move sufficiently -- if it can move at all -- such that it will set.

The problem is that this is exactly the signal that a pin has successfully set: the plug rotates very slightly, and the pin stack stops moving up. So when I think I've felt a pin set, possibly what I've really felt is just this false signal. If so, the solution to the problem is to shove the pin up harder, and I'll feel it pop out of the hole and feel the plug rotate more than before (but still only slightly if there are other unset pins in the lock). However, if I just _think_ that I've encountered this problem when in fact the pin has successfully set, then applying my "solution" will actually overset the pin.

I don't think you're listening to the lock -- you appear to be ignoring some vital feedback. When a (regular) pin sets (properly) it will make a pop or click that you can feel and often hear. If you've obtained a click and, a loss of tension in the key/bottom pin and slight rotation in the plug/barrel then you have successfully hanged the driver on the shear line.

But if the phenomenon which I'm describing doesn't actually exist, or is negligible, then I can ignore all this and know that in fact, a constant upward force on the pin will result in it successfully setting, and if the pin stops moving upward and I feel the plug rotate slightly, I can be sure that I've really set the pin and haven't encountered the problem described above.

The click or pop is important. For training purposes it may be useful to use a stethoscope or contact microphone to listen for the pops and clicks. You can get a cheap stethoscope and use elastic bands, foldback clips or aligator clips to attach the listening piece to the lock (which should be in a vise). This way you will hear the pins settings.

So my question is: do I suffer from excessive paranoia or an overactive imagination, or is the problem described above actually a real problem?

You are very analytical in your approach and where the detail is missing to make a complete (and accurate) analysis you have recruited your imagination. This is normal (for analytical types) and it shows that you are attempting to build a mental picture of what is going on inside the lock. The problem is that your analysis is incomplete. I suggest you use some acoustic aid to give you the information that you are missing. With the additional information you will be less inclined to assume and invent.

Hope this helps.