Choosing The Right Hex Allen Key For 6Mm Hex Head Screws

Hex keys, also known as Allen keys, are used to tighten or loosen bolts and screws with hexagonal heads. They are formed from a single piece of hard hexagonal steel rod, bent to 90 degrees, forming two arms of unequal length. The tool is usually held and twisted by its long arm, creating torque at the tip of the short arm, but can also be held by its short arm to access screws in tight spaces. Hex keys are designated with a socket size and are often sold in kits with a variety of sizes. The term hex key is best known as Allen in English-speaking countries and in Spanish-speaking countries such as Spain and Mexico. In Germany, the term INBUS is a registered trademark for hex keys.

Hex keys, also known as Allen keys, are used to tighten or loosen bolts and screws with hexagonal heads

Hex keys are available in various sizes, designated by the socket size, and are often sold in kits with multiple sizes. The key length generally increases with size, but not always proportionally. Some variants feature a transverse handle with multiple keys of different sizes that fold into the handle when not in use.

The "Allen" name is a registered trademark of the Allen Manufacturing Company (now Apex Tool Group) of Hartford, Connecticut, dating back to around 1910. However, the term "hex key" is commonly used interchangeably with "Allen key" in English-speaking countries like the UK, US, Australia, and Canada.

In terms of functionality, hex keys offer several advantages. They are simple, small, lightweight, and cheap to manufacture. They protect the contact surfaces of the bolt or screw from damage and allow for the use of headless and recessed-head screws. Additionally, the hex key can be used to hold the screw while it is inserted into its hole. The torque applied is determined by the length and thickness of the key, and either end of the key can be used depending on the desired reach or torque.

Hex keys are formed from a single piece of hard hexagonal steel rod

Hex keys, also known as hex wrenches, Allen keys, or Allen wrenches, are formed from a single piece of hard hexagonal steel rod. The process of manufacturing a hex key involves imparting a hexagon cross-section to a steel wire using a drawing die, then bending and shearing the wire. The resulting hex key has blunt ends that fit snugly into the similarly-shaped screw sockets of bolts or screws with internal hexagonal recesses (sockets).

The single piece of steel wire is bent to 90 degrees, forming two arms of unequal length that resemble an "L" shape. This basic design allows for versatility in how the tool is used. The long arm of the "L" shape is typically used as a handle, with the user twisting it to generate a relatively large torque at the tip of the short arm. However, the short arm can also be used as a handle when accessing screws in difficult-to-reach locations or when faster turning is required, although this comes at the expense of torque.

The simplicity and versatility of hex keys make them a widely used tool for tightening and loosening bolts and screws with hexagonal heads. They are commonly included with products that require end-user assembly, such as flat-pack furniture and bicycles, due to their small size and ease of use. Additionally, hex keys are inexpensive to manufacture and can be easily reconditioned by grinding or trimming a worn-out end.

While the term "hex key" is commonly used, it is important to note that the name "Allen" is a registered trademark of the Allen Manufacturing Company (now Apex Tool Group) of Hartford, Connecticut. The "Allen" name is often used generically for hex keys, especially in English-speaking countries like the UK, Australia, Canada, and the US, as well as in Spanish-speaking countries such as Spain and Mexico.

The tool is usually held and twisted by its long arm, creating torque at the tip of the short arm

Hex keys, also known as hex wrenches, Allen keys, or Allen wrenches, are used to tighten or loosen bolts and screws with hexagonal heads. They are formed from a single piece of hexagonal steel rod, bent to 90 degrees, resulting in two arms of unequal length. The longer arm is typically gripped and twisted, generating torque at the tip of the shorter arm, which fits snugly into the screw socket. This design provides a simple, lightweight, and versatile tool that can accommodate very small bolt heads.

The versatility of hex keys is further enhanced by their ability to be held by either end. The long arm is typically used for generating torque, while the short arm can be employed to access screws in tight spaces and for faster turning, albeit with reduced torque. This dual functionality makes hex keys a handy tool for various applications.

The tool's design also allows for the use of headless and recessed-head screws, providing a safer alternative by reducing the risk of catching on clothing. Additionally, hex keys are inexpensive to manufacture and can be easily included with products that require end-user assembly.

When using a hex key, it is important to select the appropriate size for the screw. Both metric and imperial hex key sets are available, and it is recommended to have both types in your tool collection due to the varying hardware standards across different countries. For example, a 1/4" SAE hex wrench can be used as a substitute for a 6.5 mm metric wrench, demonstrating the need for adaptability when working with different measurement systems.

In conclusion, hex keys, or Allen keys, are a fundamental tool for working with hexagonal head screws and bolts. Their design, versatility, and ease of use make them a valuable addition to any toolbox, especially when combined with a range of metric and imperial size options.

Hex keys are sold in kits with a variety of sizes

Hex keys, also known as hex wrenches, Allen keys, and Allen wrenches, are simple drivers for bolts or screws with heads that have internal hexagonal recesses (sockets). They are formed from a single piece of hard hexagonal steel rod, with blunt ends that fit snugly into similarly shaped screw sockets. Hex keys are designated with a socket size and are manufactured with tight tolerances. As such, they are commonly sold in kits that include a variety of sizes.

The rods are bent to 90 degrees, forming two arms of unequal length that resemble an "L". The tool is usually held and twisted by its long arm, creating a relatively large torque at the tip of the short arm. It can also be held by its short arm to access screws in difficult-to-reach locations and to turn screws faster, although this is at the expense of torque. The key length typically increases with size but not necessarily proportionally.

Variants on this design have the short end inserted into a transverse handle, which may contain multiple keys of varying sizes that can be folded into the handle when not in use. This type of hex key set is known as a folding hex key set.

The inclusion of a free hex key with flat-pack furniture, bicycles, and other products requiring quick assembly is now a common practice. However, the quality of such complimentary tools is often questionable. A solid, high-quality hex wrench or Allen key set will last longer and prove more useful than lower-grade "freebie" tools, which are more limited in their adaptability to other tasks.

When shopping for hex keys, it is important to buy the correct size for the task at hand. Most popular brands and reliable suppliers will be able to provide a hex key sizing chart, either included on the product packaging or at the point of sale.

The Allen name is a registered trademark of the Allen Manufacturing Company

The "Allen" name is a registered trademark of the Allen Manufacturing Company, which was established around 1910 in Hartford, Connecticut. The company was originally named Allen Manufacturing Company Inc. and produced hexagonal set screws and wrenches to fasten them. The generic terms "Allen wrench" and "Allen key" are derived from this brand name.

In 1909, W.G. Allen filed the first patent for recessed hex-driven safety screws, which were a safer alternative to fasteners that protruded from machinery. The following year, William G. Allen patented a method of cold-forming screw heads around a hexagonal die (U.S. patent 960,244). This led to the creation of the "Allen safety set screw," with advertisements for this product appearing in 1910.

Despite other hex key patents before and after this date, the "Allen" name persisted and became synonymous with this type of tool. The Allen Manufacturing Company played a significant role in the wave of adoption of the hex socket head, which was driven by an industrial safety campaign. This campaign aimed to replace the traditional external-wrenching square drive screws with headless set screws, reducing the risk of workers' clothing catching on machinery.

While the Allen brand is no longer used for hex keys, L-keys, or T-handle styles, the trademark is still owned and renewed by the Apex Tool Group, which acquired the company in 2014. The Allen name and its association with hex keys are well-known in English-speaking countries like the UK, the US, Canada, and Australia, as well as Spanish-speaking countries such as Spain and Mexico.

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