[ITEM]
04.04.2020

Beholder 2 Lever Locks

65
bek@post3.tele.dk) for sq of level10, and to an anonymous figure (sorry, but your address has been wiped outin a system crash) who sent me all the sq's. They are under test, theresults will be readable soon.

All Discussions Screenshots Artwork Broadcasts Videos News Guides Reviews. Beholder 2 General Discussions Topic Details. Dec 28, 2018 @ 5:13am Where can I find adhesive tape??? Pls help Where can I find adhesive tape??? Builders product type. Mortice locks product. Builders Chrome Plated 2-Lever Lockset - Pull and Twist Reversible Latch code. LOCSET-ST2CP-W SABS approved. Yes lock type. Mortice Locks escutcheon type. Key hole door type.

Since I have played through the game once again in the near past,incorrect things are corrected by now.

Level 2: Daggers In, Rations Out

There are some dagger-shaped carvings on the walls at this level. Theproper number is somewhere between 5 and 10 (5, if I counted exactly now),but it's unimportant. The heart of the matter is what to do with them.Clear: put one dagger in each. You'll know that you've done it, from thegreen Special Quest for this level message and a ration appearingin front of ALL these carvings. Put the rations away carefully, you mightneed 'em at level 5.

Level 3: Blind the Cats Again

Those nice almond-shaped eyes are the key for the fourth level, as Shanilstated. But if you get back all the four blue gems from the eyes, therewill be the SQ.

The fact is that I tried it only once, and did not look around heavily forbonus treasure or anything, although there has to be something. Theinformation is from Sandor Takacs (taki@mars.arts.u-szeged.hu),so special thanks to him.

Level 4: Chains of Freedom

This SQ I managed to trigger twice again, so it seems to be proper bynow. There are two chains hanging from the wall: one near theentrance to this level, which enables or disables the secret walls near,and one at the room that opens from the chamber which has heroic dwarfsayings carved on the walls. This room contains Drow Cleaver, but you'llfind it iff (math's argo: if and only if. sorry) you shut both doors nearthe one with the key. The SQ is to pull the first chain, just when thewalls are at proper position: the simplest is to run a whole circlethrough the moving walls (taking the dwarven key), and then pull thechain.

Level 5: Witch's Brew

There's a hole in a wall called the pantry, not far from the dwarves. DO NOT drink the potion (of poison) you have found there.Instead, place in five (normal) rations to get five iron ones -- and thenice SQ-signal. You should have more than enough rations till then, eitherfrom level 2 or from Dohrum whom you can allow to join (even if you drophim immediately:)

Level 6: Hatch The Stone From The Egg

Yeah, another neat SQ that might be found out. The marking `nest' is afairly telltale one: get all ten kenku eggs, and put 'em in the smallroom. You'll see that this room isn't so small at all. The reward is theChieftain Halberd +5, though I wonder who would use it two-handed(damage 2d6+5), unless against a demilich. But, since there are nodemiliches in EOB1 (not even in EOB2), it would be much more appreciatableto use `Slasher' +4 and a short sword (or a shield +2/+3),due to multiple attacks or AC improvement.

Another thing: if you leave the eggs here, you can come back here anytimewith the stone ring, or to the 5th level, with the medallion. It isconvenient to travel between these levels and level 10 through the room ofthe portals on level 7. See Level 10: Stolen eggs? for details.

Level 7: Experiment Might Be Useful

If you try anything blessed with faint chances of success, you alreadyknow this SQ, just like the ones on the two levels above. What to do issimple: put a stone portal key in each of the three niches in the room ofportals. If somebody gets to know anything not obvious about thecryptic messages that can be thus gained, send me a few words. (Whatobvious means is certainly subjective; for example, no need tosay, what `great evil lies beyond the orb'..)

Level 8: Another Rack of +5 Weapons

At level 11, you can gain Flicka +5 for your mage in the back row,but the second best missile weapons for a mage are only the adamantinedart +4 (gained on level 6) and Guinshoo +4, gained on level 1.However, the damage caused with this dagger is 7-10/7-9 points (S-M/L,assumed 18 Strength), and darts also do one point lesser maximum damage.If you could gain a dart +5, it would do 8-10/8-9 points of damageif hurled by the same character, which has a half point higher average anda much longer range. No need to say that this is only the monty-haul trainof thought, but what if this is possible?

Yes it is. Also said by John Lennon; just find the room with the 10 (or12) dart racks at the northeastern part of the level, and put a singledart in each. Be aware when stepping on the plate at the entrance, sinceeven without strength bonus, the darts shoot out doing 6-8 points ofdamage each..

Level 9: What Are These Orbs For?

Yes, does anybody know? There is a writing in front of the nicheconverting gems to keys, telling us to throw a dart through the wall.Well, not exactly this is what the writing says, but this is what we wantto do. For a jeweled key and three orbs of power. One goes to the Oracleof Devouring, vapourizing permanently, but is there anything other effect?

Level 10: Stolen Eggs?

I wonder wether those kenku eggs are not mantis eggs, since they can behatched really here. Near the room with the two portals, there is a roomwith four mantis and three niches. After defeating the monsters, try toput eggs in the niches in different orders. `Somebody' says that thecentral niche should be the first one, the niche at the far side of theroom the next, and the niche near the door is the third. However, I simplykeep putting one egg in each, again and again, and after 7 eggs, I managedto create other four mantis warriors, each wearing a magical ring. If mylogic hasn't failed me, these rings are of feather fall,sustenance and two rings of protection +2

Level 11: Proper Sequence II.

After such a long time, I am not sure at all, that this is a special questactually. (It seems not to be one) By now, however, I do can describe theproper sequence.

Till now, you should have met Shyndia the drow-elven. She explained thatthe antidote can be found in the room of the levers. However, the leversare not used (as I remember), but have a nice effect if you manage to turnthem up ALL. It's a bit more difficult than it might sound since thelevers also switch each other. If you succeed, the reward will be awand of frost. The sequence is (I hope it's correct): counted fromleft to right, pull levers 1, 3, 2, 4, 5, 8, 7, 6. There might be othersolutions, too. (In fact, any combination proves to beuseful, if you pull each lever exactly once)

You might also want to know the solution to the Proper Sequence one levelabove which has 13 written on it and has seven teleports on a corridor.Here it is:

The levers represent a mechanical display of a binary number, with the`turned up means one' rule, as follows (levers are from west to east, therightmost implementing 1 and the leftmost implementing 64, * stated forteleport):So the problem is to turn up the 1, 3 and 4 levers and turn down 2, 5, 6and 7. The state of a lever defines where the teleport just west of itwill lead to. It is not too difficult to find out the up/down effectssince there are cracks on each other wall. So, after each teleport, headsouth to determine wether you are at an even or odd numbered lever (as Iremember, crack means even, but it can be easily checked examining thefirst or second wall.) You can also see at most two teleports to the eastand to the west. If you see none, the sequence is fulfilled --congratulations! Otherwise refer to the table below to determine whereyou are. The number before the semicolon means 'with crack', after itmeans 'without crack'. Without a semicolon, don't mind the cracks. Remember, the (2,2) cell of the table might be a BIG MESS if the cracksare not so nicely placed. Also, if you know the state of levers 1, 2 and7, you can find out wether 4 or 6, 3 or 5 is your position, peeringthrough the teleports to see the nearest levers.

Level 12: Dismiss Xanathar

This is NOT a special quest for level 12, I simply wonder why Shanil couldnot use the wand of Silvias. Sure you didn't try to use it longenough, Shanil. Here we go:

When equipped by a mage (since only magi can use wands) you can use it toforce Xanie retreat a square -- and do nothing that round! Be careful,for he (it?) is quick -- nearly quicker than a magic missile :)

So use the wand and step forward instantly. Repeat it, then roundXanie to the left (rather quickly!), and when he (let'sagree by this -- although sexless, a beholder has really manful power:) steps forward you, chase him down the long corridor and after a smalldance, push him in the niche between the two columns. The effect shouldbe enthralling..

So much written, have a nice day,

Otto vonCU(h430964@stud.u-szeged.hu)

Animation of a lever tumbler lock mechanism

A lever tumbler lock is a type of lock that uses a set of levers to prevent the bolt from moving in the lock.[1] In the simplest form of these, lifting the tumbler above a certain height will allow the bolt to slide past.

The number of levers may vary, but is usually an odd number for a lock that can be opened from each side of the door in order to provide symmetry. A minimum number of levers may be specified to provide an anticipated level of security (see five-lever locks section).

History[edit]

'Double acting' lever tumbler locks were invented in 1778 by Robert Barron of England.[2][3] These required the lever to be lifted to a certain height by having a slot cut in the lever, so lifting the lever too far was as bad as not lifting the lever far enough. This type of lock is still used today, on doors in Europe, Africa, South America and some other parts of the world.

A five-lever lock which is designed to be mortised into a door. The faceplate has been removed to see the inner workings.

Design[edit]

The lock is made up of levers (usually made out of non-ferrous metals). Each lever needs to be lifted to a specific height by the key in order for the locking bolt to move.[1] Typically, the belly of the lever is cut away to various depths to provide different combinations, or the gate is cut in a different location, to provide differs. A lever will have pockets (or gates) through which the bolt stump (or post or fence) moves during unlocking.[1]

There has not always been universal agreement about which variants of the basic design merit the terms 'lever lock' or 'detainer lock' or both.[4][5][6][7] Some authors use the term 'detainer lock' to refer specifically to variants where the gates are 'open' (i.e. at the edge of the lever), rather than 'closed' (i.e. entirely surrounded by the lever).[8]

Lever locks generally use a bitted key. Some locks used on safes use a double-bitted key, as do some door locks of a type often used in Southern and Eastern Europe.

Three-lever locks[edit]

A three-lever lock is a common type of lever lock, but is generally used for low security applications such as internal doors[9] as their tolerances are much lower (there are fewer combinations of key available, so they are likely to unlock doors they shouldn't).

Five-lever locks[edit]

A five-lever lock is often required for home insurance and often recommended by the police for home security.[10] There are various grades but the current British Standard (BS3621:2007) is usually required for insurance purposes. Locksmith Valerie Olifent notes that, 'The doors of many historic churches still carry an old wooden lock although often you find that a modern 5-lever mortice lock has been installed alongside it to meet insurance requirements.'[11] BS3621:2007 requires a bolt throw of 20 mm rather than the 14 mm of the earlier British Standard.

Downhill domination iso. Most BS3621 locks have anti-pick devices built in to reduce the chance of lock picking, along with hardened bolts and anti-drill plates to reduce risk of physical attack.

Vulnerabilities[edit]

A type of lock pick used to pick lever tumbler locks

Lever tumbler locks can be picked with a tool called a curtain pick which is inserted into the keyway of the lock, and a force is applied to the locking bolt. The pick is then used to lift each lever inside the lock to the correct height so that the locking bolt can pass.

Higher security lever locks (such as the five-lever) usually have notches cut into the levers. These catch the locking bolt and prevent it from moving if picking is attempted (similar to the security pins in a pin tumbler lock).

The Chubb detector lock is a variation of the lever lock which was designed to detect and prevent picking attempts.

Lever locks can be drilled, but usually a template or stencil is required to mark the drilling point, as the lock mechanism is commonly mortised into the door and so it is harder to determine the point at which to drill.

See also[edit]

References[edit]

Wikimedia Commons has media related to Lever tumbler locks.
  1. ^ abcRathjen, Joseph (1995). Locksmithing: From Apprentice to Master. McGraw-Hill. pp. 90–93. ISBN0070516456. Lever tumbler locks are built and operate much differently than the conventional and more popular pin tumbler lock. Although they have their place in high-security applications, such as safe deposit boxes with a double-set tumbler design, they are used mostly for applications that allow a more lenient state of security. Today, they are used mostly for mailboxes, luggage, lockers, and other light security applications..
    Their biggest disadvantage, however, is that they do not allow for as many master-key combinations as pin tumbler locks.
    In a basic, fixed, lever tumbler lock design, the entire lock is enclosed in a case.. The simple lever lock has three or more lever tumblers that pivot on a post and are pushed into the 'locking' position by springs, which are bound against the case and attached to the tail end of each lever tumbler. When the proper key is inserted into the lock and turned, it raises each tumbler to the point where the fence of the lock's bolt can clear the obstruction or face of each tumbler, which also blocks each tumbler's gate. When all the tumblers are in this position, the fence can be thrown through each tumbler's gate, which pushes the bolt into the retracted position.
    In other lever lock designs, a post is connected directly to the bolt. With the lever tumbler lock, when the tumblers are raised to the proper position the post of the bolt will pass through the front gating to the rear gating and hold the bolt in the retracted position.
    There are two different ways that the lever lock bolt can be thrown. In some lever locks, the end, or uncut, portion of the key that acts as a bolt throw will make contact with a bolt throw notch cut into the bolt. The other method is to use a trunnion with a talon built on the bottom of it. In both instances, when the key is turned contact is made with the bolt throw notch of the bolt, which allows it to be retracted.
    Different types of lever locks have different tumbler designs. [Simple] lever [tumblers] with one gate [rely] on the obstruction built onto the face or front of the tumbler and its tumbler trap to lock the bolt into either the locked or unlocked position. [Other types] of lever tumbler [use] a front and rear gate to trap the bolt into either position.
    Some lever tumblers have serrated saddles, or bellies, others have false gates. These varying designs make it more difficult to pick a lever tumbler lock. Lever tumblers with false gates usually are reserved for high-security units.
  2. ^'The history of locks'. London Locksmiths Ltd. Retrieved 8 November 2011.
  3. ^Bellis, Mary (8 November 2011). 'The History of Locks'. About.com Inventors. About.com. Retrieved 8 November 2011.
  4. ^Priess, Peter J. (26 September 1979). 'A Study of Surface-Mounted Door Locks from a Number of Archeological Sites in Canada'. National Historic Parks & Sites – via Google Books.
  5. ^Price, George (1856). 'A Treatise on Fire and Thief-proof Depositories, and Locks and Keys'. Simpkin, Marshall and Company – via Google Books.
  6. ^Friend, Mick (2004). 'The Encyclopaedia for Locksmiths'. Authors On Line Ltd – via Google Books.
  7. ^Pulford, Graham (17 October 2007). 'High-Security Mechanical Locks: An Encyclopedic Reference'. Butterworth-Heinemann – via Google Books.
  8. ^Tobias, Marc Weber (1 January 2000). 'LOCKS, SAFES, AND SECURITY: An International Police Reference Two Volumes (2nd Ed.)'. Charles C Thomas Publisher – via Google Books.
  9. ^'Lockshop Warehouse'. 2 & 3 lever mortice locks are generally only recommended for use on internal doors as they do not provide adequate levels of security externally
  10. ^'Insurance company requirements The Crime Prevention Website'. thecrimepreventionwebsite.com. Retrieved 13 March 2016.
  11. ^'The Ancient Art of the Locksmith' http://www.buildingconservation.com/articles/locks/locks.htm
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Lever_tumbler_lock&oldid=933369276'
[/ITEM]
[/MAIN]
04.04.2020

Beholder 2 Lever Locks

92
bek@post3.tele.dk) for sq of level10, and to an anonymous figure (sorry, but your address has been wiped outin a system crash) who sent me all the sq's. They are under test, theresults will be readable soon.

All Discussions Screenshots Artwork Broadcasts Videos News Guides Reviews. Beholder 2 General Discussions Topic Details. Dec 28, 2018 @ 5:13am Where can I find adhesive tape??? Pls help Where can I find adhesive tape??? Builders product type. Mortice locks product. Builders Chrome Plated 2-Lever Lockset - Pull and Twist Reversible Latch code. LOCSET-ST2CP-W SABS approved. Yes lock type. Mortice Locks escutcheon type. Key hole door type.

Since I have played through the game once again in the near past,incorrect things are corrected by now.

Level 2: Daggers In, Rations Out

There are some dagger-shaped carvings on the walls at this level. Theproper number is somewhere between 5 and 10 (5, if I counted exactly now),but it's unimportant. The heart of the matter is what to do with them.Clear: put one dagger in each. You'll know that you've done it, from thegreen Special Quest for this level message and a ration appearingin front of ALL these carvings. Put the rations away carefully, you mightneed 'em at level 5.

Level 3: Blind the Cats Again

Those nice almond-shaped eyes are the key for the fourth level, as Shanilstated. But if you get back all the four blue gems from the eyes, therewill be the SQ.

The fact is that I tried it only once, and did not look around heavily forbonus treasure or anything, although there has to be something. Theinformation is from Sandor Takacs (taki@mars.arts.u-szeged.hu),so special thanks to him.

Level 4: Chains of Freedom

This SQ I managed to trigger twice again, so it seems to be proper bynow. There are two chains hanging from the wall: one near theentrance to this level, which enables or disables the secret walls near,and one at the room that opens from the chamber which has heroic dwarfsayings carved on the walls. This room contains Drow Cleaver, but you'llfind it iff (math's argo: if and only if. sorry) you shut both doors nearthe one with the key. The SQ is to pull the first chain, just when thewalls are at proper position: the simplest is to run a whole circlethrough the moving walls (taking the dwarven key), and then pull thechain.

Level 5: Witch's Brew

There's a hole in a wall called the pantry, not far from the dwarves. DO NOT drink the potion (of poison) you have found there.Instead, place in five (normal) rations to get five iron ones -- and thenice SQ-signal. You should have more than enough rations till then, eitherfrom level 2 or from Dohrum whom you can allow to join (even if you drophim immediately:)

Level 6: Hatch The Stone From The Egg

Yeah, another neat SQ that might be found out. The marking `nest' is afairly telltale one: get all ten kenku eggs, and put 'em in the smallroom. You'll see that this room isn't so small at all. The reward is theChieftain Halberd +5, though I wonder who would use it two-handed(damage 2d6+5), unless against a demilich. But, since there are nodemiliches in EOB1 (not even in EOB2), it would be much more appreciatableto use `Slasher' +4 and a short sword (or a shield +2/+3),due to multiple attacks or AC improvement.

Another thing: if you leave the eggs here, you can come back here anytimewith the stone ring, or to the 5th level, with the medallion. It isconvenient to travel between these levels and level 10 through the room ofthe portals on level 7. See Level 10: Stolen eggs? for details.

Level 7: Experiment Might Be Useful

If you try anything blessed with faint chances of success, you alreadyknow this SQ, just like the ones on the two levels above. What to do issimple: put a stone portal key in each of the three niches in the room ofportals. If somebody gets to know anything not obvious about thecryptic messages that can be thus gained, send me a few words. (Whatobvious means is certainly subjective; for example, no need tosay, what `great evil lies beyond the orb'..)

Level 8: Another Rack of +5 Weapons

At level 11, you can gain Flicka +5 for your mage in the back row,but the second best missile weapons for a mage are only the adamantinedart +4 (gained on level 6) and Guinshoo +4, gained on level 1.However, the damage caused with this dagger is 7-10/7-9 points (S-M/L,assumed 18 Strength), and darts also do one point lesser maximum damage.If you could gain a dart +5, it would do 8-10/8-9 points of damageif hurled by the same character, which has a half point higher average anda much longer range. No need to say that this is only the monty-haul trainof thought, but what if this is possible?

Yes it is. Also said by John Lennon; just find the room with the 10 (or12) dart racks at the northeastern part of the level, and put a singledart in each. Be aware when stepping on the plate at the entrance, sinceeven without strength bonus, the darts shoot out doing 6-8 points ofdamage each..

Level 9: What Are These Orbs For?

Yes, does anybody know? There is a writing in front of the nicheconverting gems to keys, telling us to throw a dart through the wall.Well, not exactly this is what the writing says, but this is what we wantto do. For a jeweled key and three orbs of power. One goes to the Oracleof Devouring, vapourizing permanently, but is there anything other effect?

Level 10: Stolen Eggs?

I wonder wether those kenku eggs are not mantis eggs, since they can behatched really here. Near the room with the two portals, there is a roomwith four mantis and three niches. After defeating the monsters, try toput eggs in the niches in different orders. `Somebody' says that thecentral niche should be the first one, the niche at the far side of theroom the next, and the niche near the door is the third. However, I simplykeep putting one egg in each, again and again, and after 7 eggs, I managedto create other four mantis warriors, each wearing a magical ring. If mylogic hasn't failed me, these rings are of feather fall,sustenance and two rings of protection +2

Level 11: Proper Sequence II.

After such a long time, I am not sure at all, that this is a special questactually. (It seems not to be one) By now, however, I do can describe theproper sequence.

Till now, you should have met Shyndia the drow-elven. She explained thatthe antidote can be found in the room of the levers. However, the leversare not used (as I remember), but have a nice effect if you manage to turnthem up ALL. It's a bit more difficult than it might sound since thelevers also switch each other. If you succeed, the reward will be awand of frost. The sequence is (I hope it's correct): counted fromleft to right, pull levers 1, 3, 2, 4, 5, 8, 7, 6. There might be othersolutions, too. (In fact, any combination proves to beuseful, if you pull each lever exactly once)

You might also want to know the solution to the Proper Sequence one levelabove which has 13 written on it and has seven teleports on a corridor.Here it is:

The levers represent a mechanical display of a binary number, with the`turned up means one' rule, as follows (levers are from west to east, therightmost implementing 1 and the leftmost implementing 64, * stated forteleport):So the problem is to turn up the 1, 3 and 4 levers and turn down 2, 5, 6and 7. The state of a lever defines where the teleport just west of itwill lead to. It is not too difficult to find out the up/down effectssince there are cracks on each other wall. So, after each teleport, headsouth to determine wether you are at an even or odd numbered lever (as Iremember, crack means even, but it can be easily checked examining thefirst or second wall.) You can also see at most two teleports to the eastand to the west. If you see none, the sequence is fulfilled --congratulations! Otherwise refer to the table below to determine whereyou are. The number before the semicolon means 'with crack', after itmeans 'without crack'. Without a semicolon, don't mind the cracks. Remember, the (2,2) cell of the table might be a BIG MESS if the cracksare not so nicely placed. Also, if you know the state of levers 1, 2 and7, you can find out wether 4 or 6, 3 or 5 is your position, peeringthrough the teleports to see the nearest levers.

Level 12: Dismiss Xanathar

This is NOT a special quest for level 12, I simply wonder why Shanil couldnot use the wand of Silvias. Sure you didn't try to use it longenough, Shanil. Here we go:

When equipped by a mage (since only magi can use wands) you can use it toforce Xanie retreat a square -- and do nothing that round! Be careful,for he (it?) is quick -- nearly quicker than a magic missile :)

So use the wand and step forward instantly. Repeat it, then roundXanie to the left (rather quickly!), and when he (let'sagree by this -- although sexless, a beholder has really manful power:) steps forward you, chase him down the long corridor and after a smalldance, push him in the niche between the two columns. The effect shouldbe enthralling..

So much written, have a nice day,

Otto vonCU(h430964@stud.u-szeged.hu)

Animation of a lever tumbler lock mechanism

A lever tumbler lock is a type of lock that uses a set of levers to prevent the bolt from moving in the lock.[1] In the simplest form of these, lifting the tumbler above a certain height will allow the bolt to slide past.

The number of levers may vary, but is usually an odd number for a lock that can be opened from each side of the door in order to provide symmetry. A minimum number of levers may be specified to provide an anticipated level of security (see five-lever locks section).

History[edit]

'Double acting' lever tumbler locks were invented in 1778 by Robert Barron of England.[2][3] These required the lever to be lifted to a certain height by having a slot cut in the lever, so lifting the lever too far was as bad as not lifting the lever far enough. This type of lock is still used today, on doors in Europe, Africa, South America and some other parts of the world.

A five-lever lock which is designed to be mortised into a door. The faceplate has been removed to see the inner workings.

Design[edit]

The lock is made up of levers (usually made out of non-ferrous metals). Each lever needs to be lifted to a specific height by the key in order for the locking bolt to move.[1] Typically, the belly of the lever is cut away to various depths to provide different combinations, or the gate is cut in a different location, to provide differs. A lever will have pockets (or gates) through which the bolt stump (or post or fence) moves during unlocking.[1]

There has not always been universal agreement about which variants of the basic design merit the terms 'lever lock' or 'detainer lock' or both.[4][5][6][7] Some authors use the term 'detainer lock' to refer specifically to variants where the gates are 'open' (i.e. at the edge of the lever), rather than 'closed' (i.e. entirely surrounded by the lever).[8]

Lever locks generally use a bitted key. Some locks used on safes use a double-bitted key, as do some door locks of a type often used in Southern and Eastern Europe.

Three-lever locks[edit]

A three-lever lock is a common type of lever lock, but is generally used for low security applications such as internal doors[9] as their tolerances are much lower (there are fewer combinations of key available, so they are likely to unlock doors they shouldn't).

Five-lever locks[edit]

A five-lever lock is often required for home insurance and often recommended by the police for home security.[10] There are various grades but the current British Standard (BS3621:2007) is usually required for insurance purposes. Locksmith Valerie Olifent notes that, 'The doors of many historic churches still carry an old wooden lock although often you find that a modern 5-lever mortice lock has been installed alongside it to meet insurance requirements.'[11] BS3621:2007 requires a bolt throw of 20 mm rather than the 14 mm of the earlier British Standard.

Downhill domination iso. Most BS3621 locks have anti-pick devices built in to reduce the chance of lock picking, along with hardened bolts and anti-drill plates to reduce risk of physical attack.

Vulnerabilities[edit]

A type of lock pick used to pick lever tumbler locks

Lever tumbler locks can be picked with a tool called a curtain pick which is inserted into the keyway of the lock, and a force is applied to the locking bolt. The pick is then used to lift each lever inside the lock to the correct height so that the locking bolt can pass.

Higher security lever locks (such as the five-lever) usually have notches cut into the levers. These catch the locking bolt and prevent it from moving if picking is attempted (similar to the security pins in a pin tumbler lock).

The Chubb detector lock is a variation of the lever lock which was designed to detect and prevent picking attempts.

Lever locks can be drilled, but usually a template or stencil is required to mark the drilling point, as the lock mechanism is commonly mortised into the door and so it is harder to determine the point at which to drill.

See also[edit]

References[edit]

Wikimedia Commons has media related to Lever tumbler locks.
  1. ^ abcRathjen, Joseph (1995). Locksmithing: From Apprentice to Master. McGraw-Hill. pp. 90–93. ISBN0070516456. Lever tumbler locks are built and operate much differently than the conventional and more popular pin tumbler lock. Although they have their place in high-security applications, such as safe deposit boxes with a double-set tumbler design, they are used mostly for applications that allow a more lenient state of security. Today, they are used mostly for mailboxes, luggage, lockers, and other light security applications..
    Their biggest disadvantage, however, is that they do not allow for as many master-key combinations as pin tumbler locks.
    In a basic, fixed, lever tumbler lock design, the entire lock is enclosed in a case.. The simple lever lock has three or more lever tumblers that pivot on a post and are pushed into the 'locking' position by springs, which are bound against the case and attached to the tail end of each lever tumbler. When the proper key is inserted into the lock and turned, it raises each tumbler to the point where the fence of the lock's bolt can clear the obstruction or face of each tumbler, which also blocks each tumbler's gate. When all the tumblers are in this position, the fence can be thrown through each tumbler's gate, which pushes the bolt into the retracted position.
    In other lever lock designs, a post is connected directly to the bolt. With the lever tumbler lock, when the tumblers are raised to the proper position the post of the bolt will pass through the front gating to the rear gating and hold the bolt in the retracted position.
    There are two different ways that the lever lock bolt can be thrown. In some lever locks, the end, or uncut, portion of the key that acts as a bolt throw will make contact with a bolt throw notch cut into the bolt. The other method is to use a trunnion with a talon built on the bottom of it. In both instances, when the key is turned contact is made with the bolt throw notch of the bolt, which allows it to be retracted.
    Different types of lever locks have different tumbler designs. [Simple] lever [tumblers] with one gate [rely] on the obstruction built onto the face or front of the tumbler and its tumbler trap to lock the bolt into either the locked or unlocked position. [Other types] of lever tumbler [use] a front and rear gate to trap the bolt into either position.
    Some lever tumblers have serrated saddles, or bellies, others have false gates. These varying designs make it more difficult to pick a lever tumbler lock. Lever tumblers with false gates usually are reserved for high-security units.
  2. ^'The history of locks'. London Locksmiths Ltd. Retrieved 8 November 2011.
  3. ^Bellis, Mary (8 November 2011). 'The History of Locks'. About.com Inventors. About.com. Retrieved 8 November 2011.
  4. ^Priess, Peter J. (26 September 1979). 'A Study of Surface-Mounted Door Locks from a Number of Archeological Sites in Canada'. National Historic Parks & Sites – via Google Books.
  5. ^Price, George (1856). 'A Treatise on Fire and Thief-proof Depositories, and Locks and Keys'. Simpkin, Marshall and Company – via Google Books.
  6. ^Friend, Mick (2004). 'The Encyclopaedia for Locksmiths'. Authors On Line Ltd – via Google Books.
  7. ^Pulford, Graham (17 October 2007). 'High-Security Mechanical Locks: An Encyclopedic Reference'. Butterworth-Heinemann – via Google Books.
  8. ^Tobias, Marc Weber (1 January 2000). 'LOCKS, SAFES, AND SECURITY: An International Police Reference Two Volumes (2nd Ed.)'. Charles C Thomas Publisher – via Google Books.
  9. ^'Lockshop Warehouse'. 2 & 3 lever mortice locks are generally only recommended for use on internal doors as they do not provide adequate levels of security externally
  10. ^'Insurance company requirements The Crime Prevention Website'. thecrimepreventionwebsite.com. Retrieved 13 March 2016.
  11. ^'The Ancient Art of the Locksmith' http://www.buildingconservation.com/articles/locks/locks.htm
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