The Allen Key (or wrench) is a brand name we have all become familiar with. We use these hex keys to screw and secure various devices but most commonly we reach for them when we take home, unpack and need to self-assemble our DIY furniture.
Around 1911, The Standard Pressed Steel Company (an American manufacturer which made shaft hangers and collars using set screws) is said to have first used the ‘unbreakable’ screw.
At that time known as the ‘Unbrako’, it became a world leader in its mass production. The founder of SPS was Howard T. Hallowell, Senior. He wrote: “For a while we experimented with a screw containing a square hole like the English screw, but soon found these would not be acceptable in this country, the US. Then we decided to incorporate a hexagon socket into the screw.” He called his method ‘the internal-wrenching hexagon drive.’
These headless set screws were well received by safety campaigners, who were keen to see them used on the pulleys and shafts in factories at that time. Headless screws were less likely to catch the clothing of workers and risk pulling them onto the running shafts.
At around the same time (1909 – 1910), William G. Allen had patented a method of ‘cold-forming’ screw heads around a hexagonal die. We don’t know if Hallowell used this same method or some other for his screws. Advertisements for the ‘Allen safety set screw’ were published by the Allen Manufacturing Company of Connecticut from 1910. The company trade marked the name ‘Allen wrench or key’ for its range of hex wrenches in 1943. The trade mark is now owned by the Apex Tool Group.
In the Second World War the push for more production of every kind saw hex or Allen keys come into even wider use. Popular science magazine wrote in 1946: “Cap screws and set screws with heads recessed to take hexagonal-bar wrenches are coming into increasing use.” The popularity of the Allen key continued to grow and it is now sold in different sizes in countries all over the world.
Contribution to Retail History
The humble Allen Key facilitated a boom in the sale of flat packed goods for home assembly and today the majority of DIY furniture sold requires this tool which is included with the original package. The development of the Allen Key also resulted in the emergence of a new kind of DIY store, of which IKEA is the best recognized around the world. IKEA and numerous other retailers have created lifestyle furniture collections that consumers can assemble inexpensively and easily, with the help of an Allen Key, in their own home.