4 fast facts about Allen keys

Do you know why you reach for an Allen key?  It’s because a company called Allen Manufacturing Company, based out of Connecticut used its own name for the trademark and patent around the time of the second World War.  What they had produced is now sometimes referred to as a “hex” key – and the emphasis really is on the word ‘key’ given the way this simple and equally affordable tool really is.

That’s because it’s more of a ‘key’ than an actual wrench, with the unique hexagonal profile slotting into the ‘lock’ that is otherwise known as the equally innovative Allen bolts, which revolutionised the run-of-the-mill square-headed bolts of the day.  The Allen bolts and fasteners feature a unique recessed head, enabling powerful torque with nothing more than wrist power and a seamless finish.  And perhaps the best thing about Allen keys is that if you lose one, the next flat-pack delivery is likely to furnish you with another.

Is your organisation or workplace new to the world of Allen keys?  Sure, you may have used one to precisely torque the headset on your bicycle, but these simple and ultra-affordable tools are now deployed across the industry spectrum – from manufacturing to mechanics, electronics and far beyond.

Here are 5 fast facts to get the beginners started:

1. Six points of contact

As mentioned above, the “hex” refers to the hexagonal shape of the tool profile, with that ‘key’ slotting into the recessed fastener head.  It is believed the Allen company initially considered a square profile to make it more universally accepted, but ultimately opted for the six-sided shape for unique appeal.  In fact, the six separate and seamless points of key-fastener contact is critical to the impressive torque achieved by the snug fit, with even more power achievable with fasteners featuring deep recesses.

2. Same tool, different names

Remember, if you hold an Allen key in one hand and a hex wrench in the other, you’re holding the same basic concept.  The fact that “hex” is used by some manufacturers is all about that trademark, which was registered in 1943 – but even Allen’s version had been around for years before that.  In fact, the basic hex-shaped profile has been around since the 1800s, with plenty of patent applications for almost identical ideas cropping up during that period of time but none gaining any real traction until Allen pushed the marketing campaign early last century.

3. It’s all about the torque

As suggested in Fact #1, the simple design is all good and well, but the secret to the torque is in the six points of contact.  In fact, the snug and unique fastener/key union is so powerful that the only ‘handle’ required to tighten and loosen with relative ease is a short 90-degree bend in the key, which in most cases is a simple and single piece of hard steel.  The result is the familiar ‘L’-shaped Allen key, with either end useable as the handle – the short handle to fit into a tight spot, and the longer one for some easy extra torque.

4. It’s also about the (small) size

In the wide and wonderful world of hand tools, there’s nothing simpler than the Allen key – basically a hexagonal rod with blunt ends.  Of course, more sophisticated versions with T-handles and ratchet mechanisms and other features are out there, but for so many jobs in confined and awkward spaces, it’s often the simplest and cheapest one you’ll reach for.  That’s because while a traditional screwdriver or a socket wrench might be your tool of choice in the best of scenarios, an Allen key is almost always the easiest and most versatile tool to use when space is tight – because once that key locks into the fastener’s corresponding recess, you’ll always find a straightforward way to turn it.

Is your organisation, business or workplace warming to the idea of Allen keys?  From the simplest L-style versions to the popular and powerful T or P-handles, convenient folding hex keys and even key-ring sets, ratcheting options, precise Allen torque wrenches, Allen screwdrivers and more, there’s no doubt you’re only a few clicks away from the perfect choice.


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