Try this. A pin that has been false set will also make a snapping sound. You should notice that a larger torque requires a larger pressure to make pins set correctly. If the pressure is too high, the pins will be jammed into the hull and stay there. As you are doing the exercises try building a picture in your mind of what is going on. The picture does not have to be visual, it could be a rough understanding of which pins are set.
One way to foster this picture building is to try to remember your sensations and beliefs about a lock just before it opened. When a lock opens, don't think "that's over", think "what happened". Pick the lock, and try to remember how the process felt.
Rehearse in your mind how everything feels when the lock is picked properly. Basically, you want to create a movie that records the process of picking the lock. Visualize the motion of your muscles as they apply the correct pressure and torque, and feel the resistance encountered by the pick.
Now pick the lock again trying to match your actions to the movie. By repeating this exercise, you are learning how to formulate detailed commands for your muscles and how to interpret feedback from your senses.
The mental rehearsal teaches you how to build a visual understanding of the lock and how to recognize the major steps of picking it. If a lock doesn't respond to scrubbing, then it probably has one of the traits discussed in this chapter.
To open the lock, you must diagnose the trait and apply the recommended technique. It can be very frustrating to spend a long time picking a lock and then discover that you turned the plug the wrong way.
If you turn a plug the wrong way it will rotate freely until it hits a stop, or until it rotates degrees and the drivers enter the keyway see section 9. Section 9. When the plug is turned in the correct direction, you should feel an extra resistance when the plug cam engages the bolt spring. The direction to turn the plug depends on the bolt mechanism, not on the lock, but here are some general rules. Cheap padlocks will open if the plug is turned in either direction, so you can chose the direction which is best for the torque wrench.
All padlocks made by the Master company can be opened in either direction. Padlocks made by Yale will only open if the plug is turned clockwise.
The double plug Yale cylinder locks generally open by turning the bottom of the keyway i. Single plug cylinder locks also follow this rule. See Figure 9. Locks built into the doorknob usually open clockwise. When you encounter a new kind of lock mechanism, try turning the plug in both direc- tions. In the correct direction, the plug will be stopped by the pins, so the stop will feel mushy when you use heavy torque.
In the wrong direction the plug will be stopped by a metal tab, so the stop will feel solid. The companion question to which way to turn a lock is how far to turn it. When opening a desk lock try to avoid having the plug lock in the open position.
Locks built into doorknobs also tend to open with less than a quarter turn. Locks which are separate from the doorknob tend to require a half turn to open. Deadbolt lock mechanisms can require almost a full turn to open. See section 9. It should be obvious how to tell the two apart. The nice feature of a lock with the springs at the bottom is that gravity holds the key pins down once they set. It is also straight forward to test for the slight give of a correctly set pin.
When the springs are on top, gravity will pull the key pins down after the driver pin catches at the sheer line. In this case, you can identify the set pins by noticing that the key pin is easy to lift and that it does not feel springy. Set pins also rattle as you draw the pick over them because they are not being pushed down by the driver pin. If you scrub a lock and pins are not setting even when you vary the torque, then some pin has false set and it is keeping the rest of the pins from setting.
Consider a lock whose pins prefer to set from back to front. If the backmost pin false sets high or low see Figure 9. It is hard to recognize that a back pin has false set because the springiness of the front pins makes it hard to sense the small give of a correctly set back pin. The main symptom of this situation is that the other pins will not set unless a very large torque is applied. When you encounter this situation, release the torque and start over by concentrating on the back pins.
Try a light torque and moderate pressure, or heavy torque and heavy pressure. Try to feel for the click that happens when a pin reaches the sheer line and the plug rotates slightly. The interesting events of lock picking happen over distances measured in thousandths of an inch. Over such short distances, metals behave like springs. Very little force is necessary. Deformation can be used to your advantage if you want to force several pins to bind at once.
For example, picking a lock with pins that prefer to set from front to back is slow because the pins set one at a time. This is particularly true if you only apply pressure as the pick is drawn out of the lock.
Each pass of the pick will only set the frontmost pin that is binding. Numerous passes are required to set all the pins. If the preference for setting is not very strong i. Basically, the torque puts a twist in the plug that causes the front of the plug to be de ected further than the back of the plug.
With light torque, the back of the plug stays in its initial position, but with medium to heavy torque, the front pin columns bend enough to allow the back of the plug to rotate and thus cause the back pins to bind. With the extra torque, a single stroke of the pick can set several pins, and the lock can be opened quickly.
Too much torque causes its own problems. When the torque is large, the front pins and plug holes can be deformed enough to prevent the pins from setting correctly. Figure 9.
Correctly set pins feel springy if they are pressed down slightly. A falsely set pin lacks this springiness. It is also possible to deform the top of the key pin. When this happens, the pin is said to be false set high. The plug is held into the hull by being wider at the front and by having a cam on the back that is bigger than the hole drilled into the hull.
If the cam is not properly installed, the plug can move in and out of the lock slightly. On the outward stroke of the pick, the plug will move forward, and if you apply pressure on the inward stroke, the plug will be pushed back. The problem with a loose plug is that the driver pins tend to set on the back of the plug holes rather than on the sides of the holes. When you push the plug in, the drivers will unset.
You can use this defect to your advantage by only applying pressure on the outward or inward stroke of the pick. The top half of Figure 9. As the pins are lifted, the picking pressure is resisted by the binding friction and the spring force. Once the driver clears the sheer line, the plug rotates until some other pin binds and the only resistance to motion is the spring force.
If the key pin is small enough and the plug did not rotate very far, the key pin can enter the hull without colliding with the edge of the hull. Some other pin is binding, so again the only resistance to motion is the spring force.
This relationship is graphed in the bottom half of the Figure. The narrow key pin can be pushed all the way into the hull without loosing its springiness, but when the picking pressure is released, the key pin will fall back to its initial position while the large driver catches on the edge of the plug hole. The problem with a large driver pin is that the key pin tends to get stuck in the hull when some other pin sets. Imagine that a neighboring pin sets and the plug rotates enough to bind the narrow key pin.
If the pick was pressing down on the narrow key pin at the same time as it was pressing down on the pin that set, then the narrow key pin will be in the hull and it will get stuck there when the plug rotates. The behavior of a large key pin is left as an exercise for the reader. Some lock manufacturers e. This tends to reduce the wear on the lock and it can both help and hinder lock picking.
You can recognize a lock with these features by the large give in set pins. That is, the distance between the height at which the driver pin catches on the edge of the plug hole and the height at which the key pin hits the hull is larger sometimes as large as a sixteenth of an inch when the plug holes are beveled or the pins are rounded.
While the key pin is moving between those two heights, the only resistance to motion will be the force of the spring. There won't be any binding friction. This corresponds to the dip in the force graph shown in Figure 5. A lock with beveled plug holes requires more scrubbing to open than a lock without beveled holes because the driver pins set on the bevel instead of setting on the top of the plug. The plug will not turn if one of the drivers is caught on a bevel.
The left driver pin in Figure 9. The driver is resting on the bevel, and the bottom plate has moved enough to allow the right driver to bind. The bottom plate slides further to the right and now the left driver pin is scissored between the bevel and the top plate. It is caught on the bevel. To open the lock, the left driver pin must be pushed up above the bevel.
Once that driver is free, the bottom plate. If you encounter a lock with beveled plug holes, and all the pins appear to be set but the lock is not opening, you should reduce torque and continue scrubbing over the pins. If pins unset when you reduce the torque, try increasing the torque and the picking pressure.
The problem with increasing the force is that you may jam some key pins into the hull. A general trick that lock makers use to make picking harder is to modify the shape of the driver pin. The most popular shapes are mushroom, spool and serrated, see Figure 9. The purpose of these shapes is to cause the pins to false set low. These drivers stop a picking technique called vibration picking see section 9. If you pick a lock and the plug stops turning after a few degrees and none of the pins.
Basically, the lip of the driver has caught at the sheer line. See the bottom of Figure 9. Mushroom and spool drivers are often found in Russwin locks, and locks that have several spacers for master keying. You can identify the positions with mushroom drivers by applying a light torque and pushing up on each pin.
The pins with mushroom drivers will exhibit a tendency to bring the plug back to the fully locked position. By pushing the key pin up you are pushing the at top of the key pin against the tilted bottom of the mushroom driver.
This causes the driver to straighten up which in turn causes the plug to unrotate. You can use this motion to identify the columns that have mushroom drivers. Push those pins up to sheer line; even if you lose some of the other pins in the process they will be easier to re-pick than the pins with mushroom drivers.
Eventually all the pins will be correctly set at the sheer line. One way to identify all the positions with mushroom drivers is to use the at of your pick to push all the pins up about halfway. This should put most of the drivers in their cockable position and you can feel for them. You want to error on the side of pushing the key pins too far into the hull.
In fact, another way to pick these locks is to use the at side of your pick to push the pins up all the way, and apply very heavy torque to hold them there. Use a scrubbing action to vibrate the key pins while you slowly reduce the torque. Reducing the torque reduces the binding friction on the pins. The vibration and spring force cause the key pins to slide down to the sheer line. A mushroom driver set on its lip will not have the springy give of a correctly set driver.
Many applications require keys that open only a single lock and keys that open a group of locks. The keys that open a single lock are called change keys and the keys that open multiple locks are called master keys. To allow both the change key and the master key to open the same lock, a locksmith adds an extra pin called a spacer to some of the pin columns.
In either case the plug is free to rotate. In general, spacers make a lock easier to pick. They increase the number of opportunities to set each pin, and they make it more likely that the lock can opened by setting the all the pins at about the same height. In most cases only two or three positions will have spacers. TED emphasizes the need for evaluator training, and particularly, for training on the professional conversations that should characterize the interactions between evaluators and teachers.
E-mail or Member ID. Forgot your password? Date of birth:. Please enter both a valid email and date of birth to continue! The TED Toolkit. Share This Article Informed by extensive research, Innovation Teams determined that an effective evaluation system should: Improve instructional and professional practice to advance student achievement; Lead directly to teachers' continuous, focused professional development and growth by addressing their skills, knowledge and needs at all levels on a career continuum, from novice to veteran; Provide opportunities for teachers to use multiple sources of evidence of effective teaching and student learning; Illuminate the context in which professional practice takes place; Empower both evaluators and teachers with clear, actionable information; Ensure fair and valid employment decisions and due process; and Invite participants into the development, revision and continuous improvement of the system.
Effective teachers demonstrate a constructivist teaching practice by: Leading classrooms that are intensely engaged in discussion, inquiry, and exploration that build shared understanding; Understanding learners as complex, social beings with values, prior knowledge, and unique dispositions; Creating authentic assessments; Emphasizing learner choice and learner control; Utilizing constructive feedback; and Focusing on knowledge construction, not reproduction.
Effective teachers emphasize the development of 21st century skills by: Embedding opportunities for problem-solving, collaboration, critical thinking, creativity, multiple perspectives; Encouraging the use of technology and digital literacies; and Promoting global awareness, interactive communication, and the effective use of real-world tools. Immersion also raises concerns about metadata privacy. And, if we choose to embrace email metadata, it presents a powerful window into how we live, communicate and love in the 21 st century.
Pingback: Internet security in Eternal Alien. Tags for this story:. Add this book to your favorite list ». Community Reviews. Showing Average rating 3. Rating details. More filters. Sort order. Apr 26, Walt rated it it was ok Shelves: other. I would not recommend this book for anyone who knows nothing about lock picking and is looking for their first how-to guide.
There are better books and YouTube videos out there for that. This book is probably most valuable to someone who has some basic knowledge and is now looking for some tips to get better. The author primarily discusses what works for him. As one might expect being written by someone from MIT the book is good on theory. The two appendixes are all but useless. In the first he spends most of the time discussing how to make your own lock picks from the bristles of a street cleaner.
I'm guessing this is not something most people have ready access to. I personally haven't seen one of these since the 80's and even if I had I doubt the dude driving it would stop long enough for me to cut half a dozen bristles off of his machine. The second on legal issues basically reprints the law is MA and states that I would guess most other states are the same yeah, no.
Its short so its worth the read if this is something your interested in. This is a strange little book. It is so full of typing errors that I would guess the author never read it. I had my first encounter with the Internet in Before everything.
The Internet was a limited number of computers connected by a network, such that you could access the content of the public directories of another computer by FTP - if you knew the name or number to call. The anarchist's This is a strange little book.
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