Locksmith glossary
Clear definitions of locks, cylinders, keys, doors, access systems, security and brands.
A precision measuring instrument used to determine cylinder sizes, door thicknesses, diameters and cut depths. It is essential when ordering a replacement cylinder: a few millimetres too many make it protrude from the door and offer grip to extraction techniques. Measuring with a caliper instead of estimating by eye is what distinguishes a correct replacement from a botched job.
It is the service request that the locksmith records, with the customer's details, the location and the description of the problem. The quality of that information determines whether the technician arrives with the right material and avoids a second visit. Sending a photograph of the lock by message helps considerably, especially when the customer does not know how to identify the type of door or mechanism.
An item in the quote that covers the technician's travel to the address, usually according to the distance and the time band. It must be communicated before setting out, not on arrival. It is one of the concepts where the most abuses occur: a serious quote includes it from the start and does not turn it into a surprise supplement once the locksmith is in front of the door.
An item that covers the technician's travel to the address, according to the distance and the moment. It must be communicated in advance and integrated into the total quote. It is one of the concepts where the most abuses are detected in the sector, with attractive telephone quotes to which a disproportionate call-out is later added. A serious quote includes it from the start.
A piece that protrudes from the cylinder and transmits the turn of the key to the lock mechanism, pushing bolts and bolt pins. It is the link between the cylinder and the rest of the assembly. When it breaks or becomes misaligned, a very recognisable fault occurs: the key turns perfectly normally but the door does not open. In those cases the problem is not in the cylinder, even if it seems so, and the lock repair involves replacing this piece.
An assembly that combines the mechanical part that operates the doors and ignition with the electronics that communicate with the vehicle. Its duplication requires the car's documentation and specific programming equipment. A piece of practical value: on many models a lost key can be cancelled so that it stops working, something especially advisable if it was stolen. The time and the cost vary considerably according to make and year, so it is best to consult with the specific details.
The traditional name for the safe intended to keep cash, much used in shops and businesses. In practice it is used as a synonym for safe, although it usually alludes to models of medium size and daily use. In establishments with takings it is best to combine it with a deposit slot, so that the cash is paid in without needing to open the box during the day.
It is usually used as a synonym for frame, although in some areas it designates specifically the visible part that finishes off the opening. In quotes it appears frequently together with frame and sub-frame, which generates confusion. It is best to specify which element each item refers to before accepting a job, especially when a complete door is being replaced and it has to be decided whether the existing casing is kept or removed.
A fixing system that uses a resin injected into the drilled hole, which hardens and holds the bolt by adhesion instead of by pressure. It offers much greater resistance than a conventional plug, especially in hollow or degraded materials. It is the right choice for anchoring grilles, safes and security strike plates, where a surface fixing would completely invalidate the installed element.
The popular name for the transponder key, and also for other keys with integrated electronics, such as those with remotes and keyless start. In automotive both terms are used interchangeably. In home locksmithing it is starting to appear in mixed systems, where the mechanical key carries a chip that allows access to be recorded or the key to be deactivated remotely if it is mislaid.
An Italian manufacturer founded in 1926 in Faenza, part for years of an international group in the sector. It is one of the most recognised brands in Europe, with electromechanical locks, security cylinders, multi-point locks and access control systems. Its electromechanical models are very common in communal entrances and communal access points, where the maintenance of the electric strike plate is usually the most frequent incident.
View the CISA pageA formal communication to the insurer of an incident covered by the policy, such as a theft or the loss of keys. It must be submitted within the period established in the contract and be accompanied by the police report where applicable and by the detailed invoice of the intervention. Many policyholders do not know that their home policy covers the replacement of the lock, so it is best to check it before ruling it out.
A holding system that immobilises the key during machining, guaranteeing that the original and the copy remain aligned in the same position. There are specific clamps according to the type of key: flat, dimple, tubular or automotive. An incorrect hold deflects the cut and ruins the copy, so using the clamp suited to each profile is an essential part of a well-made duplicate.
A key manufactured from a numeric code registered by the manufacturer, instead of being copied from an original. That code allows a new key to be obtained, perfectly fitted, even if all the existing ones have been lost. It is the usual system in security locks and in automotive. The resulting copy is more precise than a conventional duplicate, since it does not carry the accumulated wear of the key used as a model.
The numbered wheel of mechanical combination locks, which must be turned in a determined order and direction to align the internal discs. It is the classic system of safes, still much valued because it does not depend on batteries or electronics. Its drawback is the slowness of use and that it requires precision when dialling, something that generates frequent lock-outs in users little used to it.
A mechanism that opens by entering a numeric sequence, without a physical key. It can be mechanical, with a rotating dial, or electronic, with a keypad. It eliminates the problem of copies and of mislaid keys, but introduces another: forgetting the combination leaves the safe inaccessible. It is best to note it in a safe place away from the safe itself, and to change it whenever someone with access ceases to have it.
A change of the opening code without replacing the lock, by means of the procedure provided by the manufacturer. In electronic models it is usually done in seconds with the safe open; in mechanical dial ones it requires a specific tool and more skill. It is advisable after the purchase of a second-hand safe, after a house move and whenever someone who knew the combination ceases to have authorised access.
A tool with a serrated profile used to act simultaneously on several pins of a cylinder. It is used both in professional openings and, unfortunately, in unauthorised access attempts. Its effectiveness is limited to basic-range locks with wide tolerances. A cylinder with security pins and complex internal channels renders it practically useless, since it generates false catches that force the attempt to be restarted continually.
An electronic lock with a wifi or bluetooth connection that allows it to be managed from a mobile: opening remotely, generating codes, checking the access record or receiving alerts. Its convenience is obvious, but it introduces new considerations: dependence on the network, security updates and protection of the associated account. The usual recommendation stands: that it keep a mechanical cylinder as a backup.
A provisional key used during construction or renovation, and which is automatically cancelled when the owner's definitive key is inserted for the first time. From that moment, all the construction copies stop working. It resolves a very real problem in new homes: during the works, keys circulate among multiple trades and it is impossible to know how many copies were made along the way.
An action in which only the essential element is deliberately damaged, normally the cylinder, preserving the lock, the door and the frame. It is what separates a professional from someone who resolves things crudely. When the non-destructive route is not viable, the difference between replacing a cylinder or having to change the whole door lies precisely in this criterion. It must always be warned to the customer before intervening, with the fixed quote.
It is the control centre of the automation: it receives the orders from the remote and the push buttons, interprets the signals of photocells and limit switches, and governs the motor. It allows times, force and operating modes to be regulated. In the face of a general failure of the system it is the first thing to be checked, since a programming problem or a blown fuse explain many faults that seem to be of the motor.
A piece that presses on the pin from the opposite side, pushed by a spring, and that blocks the turn of the plug as long as the correct key is not inserted. It always works in pairs with the pin: one rises by action of the key and the other must end up just above the separation line. In security cylinders it is on these pieces that most of the anti-manipulation defences are concentrated.
A Spanish brand of locks and cylinders present in the national market, whose catalogue covers euro-profile cylinders, rim locks and securitand theements for the home. It is found with some frequency in domestic installations and in metal joinery. As with most manufacturers that work in euro-profile format, its cylinders can be replaced with others of a higher grade without needing to touch the lock.
View the CR pageIt is often used as a synonym for lever handle in common speech, although in precise terminology it designates a turning control, such as those of tilt-and-turn windows or those for operating blinds. The confusion is common when describing a fault by telephone. If the element is lowered, it is a lever handle; if it is turned on its axis, a crank. Specifying it saves misunderstandings when preparing the material for the intervention.
A Spanish manufacturer of locks with headquarters in the Basque Country and a history of decades in the sector. Its catalogue includes mortice locks, rim locks, cylinders and security locks for homes and buildings. It is a very established brand in the national market, with a good presence in residential construction, which makes it one of those that offers the most compatible replacements in the Spanish housing stock.
View the CVL pageThe component of the lock into which the key is inserted and which contains the coding mechanism, with its pins and counter-pins. When the correct key is turned, the parts align and allow movement. In everyday language it is called a cylinder, and both terms are used interchangeably. Its great advantage is that it is replaced independently: most of the security improvements to a door involve changing this piece, not the whole lock.
A destructive attack that seeks to fracture the cylinder to manipulate the mechanism that becomes accessible. It encompasses both snapping and direct blows. Anti-break cylinders incorporate a calculated fracture line: if they give way, only the outer part does, while the core remains intact and the door stays closed. After such an attempt the cylinder must be replaced, but the home has not been compromised, which is exactly the aim of the design.
Replacement of only the cylinder, keeping the lock and the door. It is a fast and modest-cost intervention, and the usual route to raise the level of security or cancel lost keys. The key lies in respecting the exact size: a cylinder that protrudes from the door offers just the gripping point exploited by extraction and breaking techniques.
They are the internal channels carved into the plug that correspond to the key profile and guide its entry. The more channels and the more complex their geometry, the greater the difficulty of inserting a foreign key or a manipulation tool. In high-security cylinders these channels follow winding paths that narrow the available space. If the key enters with difficulty or scraping, there is usually dirt accumulated in them, something frequent in homes near the sea.
An attack consisting of pulling the cylinder out of its housing with a gripping tool, after removing or breaking the trim. It is direct and requires no technical knowledge. It depends entirely on a factor that the owner does control: how much the cylinder protrudes from the door. A cylinder flush with the surface, protected by a security escutcheon and with anti-extraction reinforcement, leaves this method with no point from which to start.
A professional tool that removes a cylinder by pulling it firmly, used when the non-destructive opening has been ruled out and the cylinder is going to be replaced anyway. It is the legitimate version of a technique that is also used for criminal purposes, with one essential difference: here it is applied to a lock that has already been decided to change. Its existence justifies why a cylinder should never protrude from the door.
It is the length of the cylinder, expressed in two figures that indicate the millimetres on each side of the central screw, for example 30x40. It must correspond to the thickness of the door and the position of the lock. It is the most important piece of data when replacing a cylinder and also the most common mistake: a cylinder that protrudes a few millimetres too far offers just the gripping point exploited by extraction and breaking techniques.