Not all fasteners can be installed using a standard screwdriver or wrench. Some have a socketed head that fits an Allen key. Allen keys are small, hand-held, manually operated tools used to install and remove these unique fasteners. You can install or remove a fastener by twisting an Allen key in the fastener’s head if it is supported.
An Allen key, also known as a hex key, is an L-shaped tool used to install and remove fasteners having a hexagonal head. They comprise a single piece of material, usually metal, bent at a right angle.
An Allen key has hexagonal ends on both ends. As a result, you can install or remove a fastener from either end if it fits.
You can learn more about the hex L wrench name tool and compare a hex key vs. Allen Key in our guide. By the end, you’ll know the different types of Allen wrenches and which hex wrench tool is suitable for you. (Read Allen Key Sizes Chart)
What is An Allen Key?
A hex key, also known as an Allen key or Allen wrench, is a compact handheld tool created by the Allen Manufacturing Company to drive a screw or bolt by hexagonal sockets. They come in a variety of sizes, but all have the same hexagonal-shaped heads.
Some people believe hex keys are new, yet the concept for a hexagonal-shaped screw drive was first proposed in the mid-to-late 1800s. It wasn’t until 1910 the concept became a working product where William G. Allen submitted a patent for the Allen Key.
It was a cold-forming L-shaped tool name with the design of a hexagonal screw. Later, he branded the screw head as the Allen safety set screw.
Hex keys are available in a range of sizes, which are measured in across-flats (AF). This is effectively the distance between the flat side’s two opposite ends. It’s critical to select the correct hex key size, as using one that’s too large could damage the fastener or tool. (Read Best Tool To Remove Lug Nuts)
The benefits of hexagonal-shaped screw bolt heads over Phillips or flathead are many, yet they’re not always suitable for some tasks. However, there are six faces of pressure, where Phillip’s head has four. You also find there is less chance of stripping the screw.
A hex key is a tool that uses a hexagonal socket to drive bolts and screws. They’re easier to use and far less prone to stripping than Phillip’s head counterparts, thanks to the Allen key sitting inside the screw and having six faces of pressure.
Hex isn’t the only pattern to provide such benefits, as Torx is a popular alternative. Hex Keys with long and short necks are available from Monroe Engineering.
It is often here that users have a hex wrench, and is there a difference between the Allen wrench vs. hex key? Comparisons are made even when there is no difference between a hex vs. an Allen wrench. (Read Socket Sizes Guide)
Types of Allen Keys
The Allen wrench doesn’t appear to be much of a tool at first glance. It’s a piece of metal in the shape of an L. However, you shouldn’t be misled by its unassuming appearance; the Allen wrench is a powerful hand tool capable of producing enormous torque for its size.
In everyday use, no one has a complete toolkit unless they have a set of Allen wrenches.
Allen wrenches are also known as popular hex-key wrenches or hex keys and feature a hexagonal cross-section that fits hexagonal-shaped recessed holes in a machine screw or bolt and set screws.
Hex fasteners will be found in a popular range of mechanical devices and equipment from bicycles, motorbike engines, cars, and self-assemble furniture from places like Ikea.
Hex fasteners allow engine covers to be secured flush to the engine case on bikes, eliminating the need for protruding bolt heads. Most motors and machines that feature belts and pulleys have small setscrews you may only access with small special Allen wrenches.
Unlike Phillips or slotted screwdrivers, Allen wrenches feature six driving points of contact, making them easier to operate and less likely to slip or what we know as cam-out.
Allen wrenches can be contained in a set of metric and SAE fractional-inch sizes. Although wrenches can be purchased individually, it is far more convenient to buy them in sets, which are more cost-effective and include all the different common sizes depending on the size of the set you have.
You can also discover that as metric-size hex screws are more common than ever before with foreign equipment making its way into the country, you are advised to buy two sets of Allen wrenches, one SAE and the other metric. (Read Sae To Metric Guide)
One challenge of possessing two complete sets of Allen wrenches is figuring out how to keep them organized and accessible. Allen wrenches, fortunately, come in a variety of types to fit the needs of most users who want to assemble furniture or need precision engine working.
Some wrenches will be joined to a metal split ring, which keeps all of the sizes of wrenches together, although it is difficult to use an individual wrench in confined spaces unless you remove the ring is first.
Allen wrenches can come in a pocketknife-like casing, which offers additional torque, where the individual wrenches fold out, and the case serves as a socket handle.
What is Hex Key?
With so many hex screws, metric, or SAE (imperial), it is handy to find a hex wrench and the different hex keys and Allen key socket tools you can find. It doesn’t matter to the company besides a different class of tool or a unique design. Here you can find the types better suited to assembling furniture, which is best used on vehicle engines of tight spaces.
Flat End vs. Ball End
The typical flat ends are found on most hex keys and bits, as they are ideal for most uses. The key’s flat end helps it to fit snugly inside a screw head or nut. When applying a lot of force to the wrench, you should always use one of these.
Ball-end hex keys are intended for usage when a nut must be fastened at an angle. Most ball-end hex keys work within 25 degrees of the entry point, making them excellent for compact situations.
A hex key with a ball end can undoubtedly be used daily. They are, however, more prone to breaking and are often more costly to replace.
Short Arm vs. Long Arm
The vertical length of most hex keys is always longer than the horizontal length. The long-arm and short-arm modifiers show how much of a difference there is.
In the vertical direction, long arm hex keys are often twice as long as they are in the horizontal direction. On the other side, short arm hex keys are about half as long on the vertical side as they are on the horizontal.
The long end lets you reach a narrow location while using the short end delivers more torque on your socket.
Hex Key Uses
Every mechanic, electrician, and machinist should have a set of hex keys on hand. A hex screw’s small size makes it an excellent choice for any application where space is limited. Allen wrenches are used to make basic repairs on everything from furniture to cars to handheld electronics.
Hex keys are also required for modifying the settings and location of several machines and power tools. For example, hex screws are used to change the depth of our countersink drill bits. The screw can nevertheless fit into narrow areas because of this.
Unique Allen Wrench & Hex Key Tools
Much hasn’t changed how the Allen key was designed or the hex design besides the application.
T-Handle wrenches are designed to provide the user with increased reach and leverage. Car mechanics and machinists frequently prefer T-handle wrenches over other hex wrenches.
Ratcheting hex drivers deliver speed compared to traditional Allen wrenches. In addition, ratcheting drivers are dynamic as a tool as they can be used with screwdriver bits & sockets.
Folding Hex Keys
Folding hex keys are popular among bikers and motorbike riders because of their compact shape. Because they’re contained in the handle, a folding hex wrench is nearly impossible to lose but easy to use and comes with all the standard sizes you need for your bikes.