Let’s talk about screws. We’re talking large screws, small screws, tiny screws, micro fasteners, and bulk screws. There is something they all have in common. They were created by screw manufacturers. That’s right, screws are not a natural phenomenon. There is no such thing as screw hunters or screw farmers.
But how do screw manufacturers produce the millions of tiny fasteners that (literally) hold our lives together, each with precision and detail? Well buckle up, we’re about to give you an overview of who screw manufacturers do their thing:
A Day in the Life of a Screw Manufacturer
- A Brief History Lesson
The basic idea of a screw has existed for over 2,000 years, but they weren’t made of metal, like the ones we know and love, until the Renaissance era. Even then, each screw had to be filed down by hand. As you can imagine, this was labor intensive work, and goods were made with as few screws as possible. It wasn’t until 1586 A.D., when a court engineer for King Charles IX of France created the first screw-cutting machine.
The next big leap in screw manufacturing took place in 1760, when a pair of English brothers named Job and William Wyatt were awarded a patent for an automatic screw-cutting machine. This device could create ten screws every minute, a mind-blowing speed in its day and age.
Now our tale fast-forwards to the eighteen-hundreds, when good ol’ Henry Maudslay created the first power-driven screw cutting machine. He was in England at the time, and across the pond in the United States at the same time, an American gent by the name of David Wilkinson was awarded the first American power screw manufacturing patent. His design was similar to Maudslay’s invention, and the screw-technology used today is based upon this.
The one distinction between what was used to create screws back then and now is that screws of yester-year were machined, while now-a-days screws are created with the thread rolling process. This swift change in screw-making came to be once the iron that was used for thread-rolled screws was replaced with a higher-grade material, which prevented them from splitting. Thread rolling enabled screw manufacturers to produce screws in mass, at a fraction of the cost.
- Material Matters With Screws
Thread-rolled screws are usually made of a carbon steel wire, but sometimes they are made of stainless steel, alloy metals, or brass. The quality of metal used in the process is one of the greatest factors in the quality of the screw, and the cost to produce them.
- How Made Screws are Made
The screw-making process goes a little something like this:
- First, wire is run through a machine to straighten it out. This machine also cuts the wire at the length needed to create the designated size of screw, and the head of the screw blank is die cut into the shape it is to have. This step is very fast, and the machine can spit out as much as 550 screw blanks in a single minute.
- After the screw blank is created, they are automatically fed into a machine via vibrating hopper. This machine sets the blanks up to become bonafied screws in the next step. That involves putting them into the right position to be threaded.
- Now, the screw blanks grow up to be certified screws through one of three techniques. If a reciprocating die is used, in which one die is still, and then another moves in a reciprocating pattern, and the blank in-between takes on the pattern of the final screw. Sometimes the centerless cylindrical method is used. In this case, up to three round dies are used to roll the blank into the final thread. The third threading method is called the “planetary rotary die” process. This process involves the screw blank be stationary, while the dies rotate around it.
All three of these methods produce very precise results in huge quantities, with very little waste and expense. These processes involve pressing the shape into the blank, rather than cutting the thread out, which wastes material and leads to split threads. These processes are capable of creating a whopping 2,000 screws in a single minute.
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