Want to buy an old bicycle from **** Jingmen

Making your own locks and modifying existing locks by yourself is a test of ability and is the foundation of the country. The specific measures are detailed below:

The security guard in this community was arrested again After arresting the car thief, we seized hydraulic pliers, which break ordinary locks after shaking them three times. The length of the pliers is one foot long, as well as various keys for forced opening. After learning the news, I launched another social investigation. After seeing several brand-new hydraulic pliers, I decided that it would be better to make my own locks. For ordinary citizens, the best strategy is to purchase an idle lock, and then weld some steel bars or pipes to the lock body and lock hook. If the equivalent outline diameter and size exceed the opening of ordinary hydraulic pliers, you can rest assured. Pay attention to the body and fixed objects. Cuffed together.

Reporter:

The following are practical and effective security precautions. They have no commercial content. They are updated based on the content added to my old posts and have wide application value. This is a public welfare post, please let the network administrator release it.

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If you were the police chief, how would you deal with bicycle theft?

Report to the head:

In response to the teachings of the great leader Chairman Mao, the selection and training of cadres is the key to the success or failure of the revolution. How you choose the locks of your vehicle determines the safety of your private property. Now come to serve the people and provide effective guidance. It also has broad guiding significance and does not contain any commercial information from the manufacturer. Please review it by the chief:

Nowadays, people who do bad things are so bold that they are not afraid of your anti-theft alarm!

The wiring positions of electric vehicles are all open to the public. They were cut with a knife and became mute on the spot! Rigid anti-theft devices are more reliable in the physical sense. Those "high-tech alarm products" are virtual. If you are indoors when the alarm is raised, or connected to the local security department, someone will come to check immediately. It is okay to use standard The equipment, wiring methods, well-known alarm principles, and familiar appearance of the equipment that are well-known on the market are not as reliable as non-standard and homemade equipment.

It has been fully answered under the post you asked "What feasible suggestions can be adopted by the relevant departments to put an end to bicycle theft? Thank you". Because the detailed information of the production company is involved, the network administrator has published an advertisement. delete. Websites should also learn from the Scientific Outlook on Development and publish original investigation reports on major issues involving public interests.

In the public security department, before the reform and opening up, there were lock detection and lock production management departments. The locks produced must be evaluated by the public security department for safety.

The public security department is very aware of the various methods used by thieves to destroy locks.

In the early days of reform and opening up, many people called for strengthening the safety of bicycle locks. There are indeed many such products. The several locks I use only need to lock the bicycle to a fixed water pipe or a fixed traffic sign pole. , on the fixed handrail, thieves really can't open it, they can't break it without cutting. The specific contact address of the relevant enterprise is not allowed to be issued by the network management.

Nowadays, there are stainless steel bicycle locks, idle locks, Z-shaped keys, ∏-shaped keys, and carburized and hardened lock hooks. The characteristic of the idle lock is that the lock cylinder can be turned with ordinary tools, keys, and iron sheets. A key made of high-strength steel cannot be forcibly opened; and the original key can open the lock.

There are thick iron pipe lock bodies, copper lock bodies, and locks produced with imported German technology.

Generally, locks with a wholesale price of 35 yuan or more are sufficient, and locks with a wholesale price of 70 yuan/lock are the highest security level.

There are motorcycle locks on the market with a wholesale price of 100 yuan/piece.

Generally, the wholesale price of a lock is 50 yuan/lock, and it can be purchased at a retail store for 120 yuan/lock to 180 yuan/lock. The ex-factory price of a motorcycle lock hollowed out of square iron was more than 60 yuan/box, and it was still more than 20 yuan/box a few years ago; the motorcycle lock made of copper used to be more than 30 yuan/box, but now it is more than 100 yuan/box. /handle, if environmentally friendly copper materials that meet recent European requirements are used, it will be more expensive.

Taobao has push-button digital password bicycle locks, which used to be 60 yuan per lock.

Just go to the motorcycle parts wholesale city near where you live and look for it. Merchants will not tell the truth, so make your own judgment.

Bicycle locks currently sold in bicycle sales stores and bicycle repair stations are basically unsafe.

Several brands of locks recommended by netizens are only safe when they are high-end locks from the original factory. The market agrees that buying from the same brand is not acceptable.

The bicycle locks recommended by some small local public security bureaus are still low-end locks, and the profit of the merchants is half.

Therefore, if there is no access system for the sales and production of low-end bicycle locks, it is endangering public interests.

So, this is the job of the public security department, the Industrial and Commercial Bureau, and the Quality Supervision Bureau, and it needs to be led by the government.

No one can open a good lock if it is broken by prying. It can only be cut with an electric grinder. You can choose unconventional shaped keys to reduce the possibility of being stolen by thieves. You can also Choose a less secure lock to lock your bike to a fixed object.

The former has no jobs, but the latter monopolizes resources and power is endangering national security!

The biggest obstacle is that those who are capable are not allowed to do it, and those who are incompetent are not allowed to do big things. The rights, instruments, and resources are all in the hands of mediocre people. It's not a matter of salary, but there are no positions at all, and you can't enter the laboratory or use ordinary instruments that are idle. The problem you raised would be very easy to eliminate if Zhou Enlai were to revive it. Moreover, there are already locks on the market that meet your requirements. From molds to production lines, they are all existing. There is no need for further scientific research, development, or investment. In the hardware market, bicycles, etc. The retail market is completely invisible, and the public has no ability to judge and investigate.

A few simple suggestions:

Do not install the lock firmly on the bicycle body, as this will make it easier for thieves to exert destructive force.

The diameter of the lock hook should be greater than 15 mm. It is generally made of low carbon steel. Those with a wholesale price of less than 25 yuan are not carburized and are not hard enough and can be cut. Those that are carburized are called "carburized" on the product. "Hardened type", another way to judge whether it is carburized is to use a manual saw blade, a steel saw blade, a saw blade with a length of 300 mm, a thickness of 0.64 mm, and a width of 12 or 13 mm to manually saw the lock hook and carburize it. The lock hook cannot be sawed in. The saw blade keeps slipping on the lock hook. The effective diameter of the iron chain is calculated based on this. Iron chains generally do not carburize. Stainless steel can be thinner because stainless steel is soft and tough and difficult to cut. Generally, metal pipes with a diameter of more than 20 mm and a wall thickness of more than 1.5 mm cannot be cut continuously. At least the opening of ordinary scissors is not that big. Even if the opening is large, because the levers are tilted toward each other, there is not much left. Shear force can be applied, and it is slippery, you can use the tap water pipe.

Open the lock hook and turn the key. You can see the part in the lock body that jams the lock hook - the lock tongue. Steel balls with a diameter of more than 10 mm are the most reliable. Generally, the lock tongue is made of low carbon steel punching. , the thickness is less than 2 mm, and the width is less than 15 mm. The lock tongue extended by the copper lock core is also not impact resistant.

You need to bring a magnet to pick out the lock body, and the lock body needs to be made of iron, and the thickness of the lock body tube must be greater than 2.0 mm, otherwise the pin will not be strong. Those lock bodies with embossed fonts are usually made of zinc alloy die-casting, which is too fragile.

Locks made of a whole piece of copper are basically not produced now. They cost 80 yuan/box to 150 yuan/box and are quite heavy in the hand.

In reality, a better lock body is machined from a whole piece of iron, with a cavity dug out using a milling machine or lathe, rather than a cheap product cut and processed from square or round tubes.

Originally, cross keys and crescent keys are acceptable, but in fact many locks have a small number of marbles, a small range of travel (the height difference between the teeth is large), and do not even require a spring return. The copper lock cylinder is made of copper. If the brand and material are poor, the diameter of the marbles is small, the number of marbles is small, and the height of the marbles is low, it will be unreliable.

Generally, you can find a key with teeth on both sides, a square rod, and a key with notches milled on both sides.

The sleeve-shaped key also depends on the number of marbles, the height of the marbles, and the firmness of the pin.

The best locks are original ones, which can improve the level of China's industrial base. It is recommended to carry out a national system, a national competition, and a big competition. I have seen some bicycle locks made by bikers. This truly reflects the basic industrial level of the nation. What is really kept secret are the high-precision, abnormally structured locks that we make ourselves, and they are not in the market.

For example, the locks of the Beijing collider require two people to use mechanical keys to open them at the same time. The cockpit locks of military aircraft and the locks of prisons are all customized; the communications of military, diplomatic, and government departments of various countries Security machines are all designed and produced by the country itself. As a major sovereign country, this device is not imported for use in key departments.

I have published papers on crime prevention in English at international academic conferences. The above is daily life knowledge.

Hydraulic pliers are now popular, and the ordinary lock hook with a diameter of 15 mm. The blade of the hydraulic pliers is pressurized and enters the lock hook less than halfway, and the lock hook breaks! ! ! Domestic hydraulic pliers with a maximum opening of 12 mm cost 360 yuan a pair; a maximum opening of 16 mm cost 390 yuan a pair. There are also ones with an opening of 14 mm. Generally, the retail price of a pair with a maximum opening of 20 mm can be 350 yuan. Imported ones have manual hydraulic openings. 80 mm. Use hydraulic pliers in remote and dark places; use rigid keys to open in crowded places.

It is better to make a homemade lock hook with a diameter greater than 20 mm. It can be a pipe lock hook, or use a good lock and add one or more steel bars welded to the original lock hook, or put it on the faucet iron pipe. The cutting edge of the current lightweight hydraulic pliers cannot be opened that wide. Pay attention to the fact that if the lock body and the lock hook are connected by a joint or hinge, or the lock hook and the lock body are separable, there must be a suspended shielding, widening, and strengthening part at their joint part. , to prevent thieves from setting pliers here. For the zinc alloy lock body, the zinc alloy lock body package has been welded to an iron shell. The lock hook is made of three construction site threaded steel bars with a diameter of more than 12 mm. The lock hole is welded with a curve of more than 1.5 mm thickness. To open the lock, the key must be turned from the side and stretched into the keyhole to prevent illegal intrusion of the key by force opening the straight bar. After locking it with a fixed object, people who park in various places and deliver goods every day have proven safe after several years of practical assessment. reliable! ! ! ! !

For the assessment of the safety of locks, the first step is to determine whether the lock cylinder can be violently unscrewed. After all, ordinary people cannot judge. You can type the keyword "idle rotation lock" online and purchase this kind of lock first. , its characteristic is that when a general lock key or screwdriver is inserted into the lock cylinder, the lock cylinder can be rotated freely, but the lock cannot be opened. Then use iron pipes, steel bars, and stainless steel pipes to weld and reinforce the lock body and hook.

For residents living upstairs, you can see if you can use a water pipe to make a lock hook, use a hammer to drill two large holes in the wall, and pass the lock hook to the other side of the wall. Lock the hook with a lock on the other side of the wall, but make sure that non-residents cannot reach the other side of the wall. It should be noted that manual pipe cutting tools were born 50 years earlier than hydraulic pliers. Although the lock hooks made of water pipes are beautiful and neat, medium-diameter steel bars should be welded on them to prevent manual cutting of pipes, because the surface of the water pipes is hot-plated Zinc cannot be welded by burning zinc during direct welding. You must first use an angle grinder to remove the galvanized layer at the welding position.

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There are many kinds of keys, how to design and produce them

There are so many locks in the world, which means that there are also so many keys. Just so that others can't open it, how can every key be made different? Even if some are universal, the majority are still non-universal. Do we need to design every key?

Each type of lock has the same key blank

According to the programming, during the production process, the interception length of the lock core pins is matched with the key drilling and milling depth, according to the arrangement and combination , can match thousands to hundreds of thousands of locks and matching keys.

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Does anyone know the principle of matching a key with a lock?

It’s very simple.

The first is the manufacturing accuracy of the lock cylinder, pins and keys. For example, within the specified stroke, that is, the difference between the highest tooth bottom and the highest tooth bottom, can The number of subdivided steps may be 100 for a precise one, and 20 for a poor one. If the accuracy cannot be improved, no matter how high the number of steps is, it is meaningless. Adjacent numbered keys have interoperability; the tooth shape of the key changes (tooth pattern). No.) are relatively small, so the probability of keys with similar key tooth shapes opening each other is very high.

What is the arrangement and combination of two marbles? What is the arrangement and combination of three marbles?

Middle school students can do math. For example, each bead has 10 height levels, a lock with 2 beads has 100 combinations, and a lock with 3 beads has 1,000 combinations.

The structure of those low-end bicycle locks may have hundreds of codes, that is, hundreds of keys; the structure of high-end locks may have hundreds of thousands of codes, that is, "numbers". For example, imported locks are manufactured with high precision, and each pin can have two layers; a large hollow pin with a small solid pin inside, and then rely on gravity to swing the independent pin to improve safety. Compared with European, American and Israeli locks, Taiwan's locks are less accurate.

Some low-end bicycle locks can often be opened immediately with a high-strength key, which has nothing to do with the number of key combinations in the design of the lock. As for the steel wire braided lock hook, the effective diameter must be quite thick to be reliable. The effective diameter is less than 12 mm to 15 mm, which is dangerous. The apparent diameter cannot indicate the actual effective diameter. The key quantity of the lock safety performance assessment index is the design accuracy, and the mutual opening rate reflects the actual processing accuracy.

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Anti-theft doors and windows

Our family lives in a bungalow. Now we want to install anti-theft doors and windows, but we don’t know what stainless steel and Which type of aluminum alloy has the best anti-theft effect? ??If you know, please analyze it. Thank you! ! !

If you have money, use hot-rolled solid stainless steel (there are specialty stores, it costs 20 yuan per kilogram), with a diameter greater than 10 mm, an oxide layer on the surface, and no pickling. A layman thinks it is ordinary stainless steel. The painted mild steel is grade 201, and the ingredients can be mixed to make it more difficult to cut. You can also use high-carbon steel or alloy steel rods as mold materials (there are specialty stores). Pay attention to the hardened ones when supplying them. The thickness of the middle and upper and lower spacers should be greater than 3 mm. It is easier to drill holes in the angle iron and pass the iron rods. Specifically, it is safe to use angle iron with a side length of more than 25 mm and a thickness of more than 2 mm for the spacers. The spacers need to be welded to the iron rods. If it is high carbon steel, it will be difficult to weld and it will crack after welding. Unless it is preheated before welding, it is necessary to lengthen the steel rods at the upper and lower ends.

The price of stainless steel and aluminum alloy anti-theft doors and windows is comparable to the above standards. Ordinary low carbon steel is more expensive and has lower strength. To do so, you must first ensure that you feel at ease and at ease.

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What equipment should be used to prevent theft?

I have an open-air patio with three walls, and I want to install anti-theft equipment to prevent outsiders from entering!

I want to install an anti-theft device that can automatically alarm when someone passes by. What kind of device should I use?

Purchase stainless steel wire with a diameter of 0.8 mm or more. Generally, 1 mm and 2 mm specifications are common.

Weave a large-hole net according to the environment to block possible passages.

The maximum diameter of the hole is smaller than the cross-section of the human body. The particular method is to insulate each intersecting longitude and latitude lines from each other. It is best to use ceramic mechanical connections and electrical insulation, or to use insulating materials that are resistant to sunlight, ultraviolet radiation, and are not prone to aging.

Then use ordinary disconnection and short-circuit measurement circuits to interpret each longitude and latitude line, which is a reliable anti-theft system. It is very reliable in heavy rain, snow, and ice environments! ! ! ! 201 stainless steel wire that will rust is about more than 20 yuan per kilogram, and 304 stainless steel wire that does not rust is more than 40 yuan per kilogram. You can use ordinary copper core wires or telephone wires. Iron wires have poor weldability, so use stainless steel gas. Protective welding. The simplest method is to connect all the longitude and latitude lines in series, so that there are only two thread ends in the end. When they are disconnected, the alarm will be triggered. Advanced bridge balancing can be used to judge, and local short circuit will also alarm. Note that the nodes where the longitude and latitude lines intersect must be insulated and tied with insulating materials to prevent thieves from easily untying them. By nailing this kind of net to the interior wall, you can also know if someone has drilled a hole in the wall from the outside to steal livestock and other property. At this time, you need to use thin wires with poor mechanical strength.

Do-it-yourself car anti-theft is the most reliable! ! ! ! ! ! ! !

Install alarm fireworks launch devices, automatic smoke combustion devices, and self-destruction and self-destruction devices! ! ! ! Eject the radio into the air to emit an alarm signal.

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Is there any kind of guardrail that can protect against theft and is allowed to be installed on the property?

In Many residential areas in Beijing do not allow the installation of anti-theft guardrails for the sake of appearance. At the same time, if the external anti-theft nets are installed, it will affect the harmony between neighbors and become a tool for thieves to climb! If the old-fashioned anti-theft windows cannot be opened in an emergency and the maintenance of the air conditioner is affected, is there a more humane anti-theft window?

Use the above stainless steel wire to weave the net, which can be curled and folded. When a fire occurs, use pyrotechnic equipment to generate high-pressure and high-temperature jets to cut the anti-theft net, similar to explosive bolts; or use electromechanical Install the release mechanical lock.

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Which is the best smart anti-theft lock made in China and used on home anti-theft doors without a mechanical keyhole? kind?

Designing and manufacturing by oneself is a true reflection of national quality, especially in an era when more private individuals with ordinary salary levels can complete tasks independently.

The presence of keyholes provides opportunities for artificial damage such as inserting toothpicks, squeezing in adhesive, etc.

The input board and camera of the fingerprint lock have poor resistance to human damage.

Because I have been laid off and unemployed, I cannot guide students to implement at my own expense. This is not my fault.

Relevant substantive information has been disclosed internally.

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Who has any tips for preventing theft if the car is left downstairs without a lock?

Because there is no place to put the motorcycle and battery car at home, I put it in front of my house. It is a two-story private house. It has been visited by thieves many times. Now I hate thieves so much that I sleep every night. It’s not peaceful. There is still a tricycle at the door of my house but it is not locked. (One was stolen even though it was locked.) There is also no alarm. Does anyone have any tips and advice...

Regarding your problem, the simplest way to prevent it is to open two holes in the wall at appropriate locations. This is to purchase a thick enough water pipe and a right-angle elbow, connect the water pipe into a ∏ shape, and open a through hole at the opening position. Insert the opening into the wall hole, add a lock in the hole where the water pipe runs through in the direction of the inner wall, or insert a pin into the hole where the water pipe runs through. Note that after the water pipe is assembled, the joints must be welded to prevent them from opening, or a long pin that runs through the two water pipes can be inserted into the opening of the water pipe to prevent external disassembly. It can also be welded with steel bars, which requires the total equivalent diameter of the steel bars to be greater than 20 mm.

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Some questions about invisible anti-theft windows

1. The gap between the steel wires is several centimeters, and the thief is not there Can I get in through the gap if the wire is broken?

2. My home is on the second floor (the first floor is the garage). Is it suitable to install an invisible anti-theft net?

3. Is the invisible anti-theft net 100% safe? Do thieves really care about invisible anti-theft nets?

Of course, physically strong anti-theft windows are the most reliable. If you spend money on electronic waste, they are not as reliable as traditional steel bars. If you have money, go to the mold material supplier to buy various mold steel bars. There are many materials and heat treatment effects that even hydraulic pliers can cut continuously! ! ! ! ! ! ! The Yangtze River Delta region and the Pearl River Delta region (such as Dongguan) all supply large quantities of products. Your opponent is a hydraulic plier

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Lock cylinder price

Mechanical locks generally have a lock cylinder with an internal A lock cylinder that can be turned with a specified key.

The most versatile, some lock stores and key repair workshops have this type of lock core. A slightly better one made in China generally costs 30 yuan, which varies; the starting price of an Israeli invincible lock core is 30 yuan. The price of each lock cylinder is 300 to 400 yuan. The Israeli lock cylinder and the American lock cylinder have a threaded structure and are locked with screws on the longitudinal grooves on the outer circumferential surface. Generally, a lock cylinder costs more than 1,000 yuan.

The outer diameter of this type of lock cylinder is the same, but there are several differences: the connecting rod driven behind the lock cylinder and the lock cylinder are divided into two types: concentric and eccentric. Special attention should be paid to the safety of eccentricity. Higher, it enhances the resistance against thieves to open the lock. In addition, the length of the lock cylinder is different. For a long lock cylinder with a thin door, it is necessary to use a professionally produced thick washer in front of the door to raise it. If you make it yourself, you can simply weld one piece (or stack several pieces) to make it thicker. The outer edge of the iron ring should be greater than 10 centimeters. The bigger the better, as it is safer against damage and disassembly of the lock; you can also raise the lock seat inside the door.

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Anti-theft at home

My house is always stolen~~either the lock is broken or the door is broken , report it to the police. Now the police won’t do anything if they don’t give you money. . . . . . They are all farmers and ordinary people, and they don't care at all. Yesterday I went out to work. When I came back in the evening, I found that my computer had been stolen. Please call the police. The police asked me for an invoice. If I didn't have a computer, the invoice would not be processed. But I didn't ask for an invoice when I bought the computer, so the police Regardless of this matter. I'm very sad. My bedroom has been stolen four times. I have to go out to work. I can't watch it at home all day long. So I want to install a monitor like the one on the TV. But I don’t understand, what should I say? What to buy? What's the name of that monitor? Can you help me? Hey, this world is so crazy, I want to install one of those things in my home, who can help me? Thank you

Additional question: I am a farmer’s child, and my family doesn’t have much money. I just want to make some noise. I hope everyone will consider my financial situation and give me a suitable monitor, as long as it is the kind that can monitor everything during the day. The kind that records everything from day to day would be good. It would be better if it is compact and concealable. Thank you. I'm about to cry. Why doesn't anyone give me a satisfactory answer?

The standard saying is to dig a cellar and bury treasures when traveling far away is to clear the field with strong walls.

Or dig a tunnel under the police station, build a storage room, and connect to the police station.

Or just dig in front of the police station. Anti-theft devices, cameras, hiring security guards, renting warehouses, and renting bank safes are all free. The safety of locks, door locks, and anti-theft doors is measured by the time it takes to break them, which is much better than them.

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The wall is made of hollow bricks. How do the expansion bolts bear force?

I install invisible anti-theft nets, and I often encounter hollow brick walls. The M6*80 expansion bolts are driven in, but they are still loose.

I don’t know if there is any good way?

Grout! ! ! ! ! ! ! ! Especially pouring expanded cement

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On the issue of installing anti-theft windows

The baby can already walk, and the windows at home It's quite low, and it's impossible to watch him 24 hours a day for fear that he will climb into the window. Do you think it is necessary to install anti-theft windows?

Life is the most precious! ! ! ! ! ! ! ! !

First use nylon rope to make a mesh with multiple layers. In order to prevent the baby from being injured by the metal wire, it is easy to use a metal mesh with a small diameter.