During the 17th century, the graphite and clay were grounded down by hand, put into a cylindrical mold, and fired in a kiln. Today, pencils are mass-produced by machines that cut down the wood, insert the lead, and stamp or print a design. We couldn't complete a crossword puzzle, sketch a masterpiece, or write the next great American novel without a good pencil.
While it may seem like these writing instruments simply grow on trees, they require expert craftsmanship and engineering to be produced. Since pencil's early days, the manufacturing system has more or less been the same. The graphite is grinded down and mixed with powdered clay and water to make a thick paste. This paste is put into a cylindrical mold and fired in a kiln. The result is a strong lead core that's difficult to break and extremely smooth for writing on paper.
Source: Pencils. A system for grading the graphite was eventually developed in the s. Henry David Thoreau and his father John numbered the hardness of their pencils from 1 - 4.
The softer the pencil, the more graphite it contained, resulting in a darker, smoother line. The firmer the pencil, the more clay it contained, meaning the lines would be lighter. The standard today, as any student can verify, is the reliable 2 model. The graphite in these pencils is at just the right amount of thickness to produce an easily readable mark. With Thoreau's scale in place, America needed a way to keep up with the demand for high-quality pencils.
In the s, Joseph Dixon used his background in lithography to create machines that were capable of mass-producing pencils at a faster rate. The machines also pushed the pencil making process forward by cutting grooves for the graphite into the wood. Before then pencils had always been handmade with a flat, round design. With Dixon's machines, they were hexagonal and had attached erasers. His company could produce upwards of 80, a day, completely taking the industry to new heights.
Many pencil-making companies are in Tennessee, harking back to the old days when they set up shop in this area to have easier access to the valuable red cedar oak.
The best trees are around years-old since they're mature enough to be cut. By the time the tree is chopped down and ready to go, each manufacturer follows a similar format in creating the pencils. The first step is making sure the wood is soft enough to sharpen, but not so soft that it will bend when you use it to write.
The wood is pre-cut into slats called "pencil stock" or "pencil squares" at sawmills. Each slat is placed in a dry kiln prior to being shipped to the manufacturer. This gives them a uniform moisture content that makes their assembly more streamlined. The manufacturers apply a wax and stain after they receive the slats from the sawmills.
The first ancestor to more familiar pencils was invented in , after the discovery of graphite abundance, in Borrowdale, England. While wrapping the lead in string did not prove to be the most practical solution, inserting it into wooden holders, solved the problem. In , Nuremberg became the first city in the world to mass produce these early wooden pencils. Pencil casings are made out of softwood , harvested from the trunks of coniferous trees, such as pines, spruces, and cedars, with the latter being most commonly used in the pencil production industry today.
The cedar tree needs to be at least 14 years old, before being felled, logged, and cut into 7. Another slat is placed on top, acting as a casing to wrap snuggly around the lead. The slats are then heated and pressed together, becoming one long sandwich, which is cut into 9 individual pencils. A large percentage of cedar wood designated to pencil-making for distribution around the world is grown in Sweden and South Africa. More than 14 billion, enough to easily circle the globe about 60 times. On average, we may calculate that around , pencils can be manufactured out of a single tree.
Since according to the same source around 15 billion pencils are made every year, this means that around 64, trees need to be cut every year to produce pencils. History of writing instruments, pencils and pens, is thousands years long.
We us pens, in one form or another, since the First Dynasty of Ancient Egypt while the pencils are much younger but nothing less important. Pencils need sharpening at regular intervals, they can smudge and smear and leave grey marks all over your hands. Also they can be erased by other people. Pencils are better for shading. Marks made with pens last longer. Some pencils have erasers, which are held on with a ferrule, a metal case that is either glued or held on with metal prongs.
The erasers themselves consist of pumice and rubber. Now that most commercially used graphite is made in factories rather than mined, manufacturers are able to easily control its density. The graphite is mixed with clay according to the type of pencil being made—the more graphite used, the softer the pencil, and the darker its line.
For colored pencils, pigments are added to the clay, and virtually no graphite is used. Colored pencils are produced in much the same way as black-writing pencils, except that their cores contain coloring materials such as dyes and pigments instead of graphite. First, clay and gum are added to pigment as bonding agents, and then the mixture is soaked in wax to give the pencils smoothness.
When the pencils have been formed, the outsides are painted according to the color of the center mixture. Because they travel along a conveyor belt during the manufacturing process, pencils are thoroughly scrutinized before they are distributed to the public. Workers are trained to discard pencils that appear dysfunctional, and a select number are sharpened and tested when the process is complete. A common problem is that the glue of the sandwiches sometimes doesn't adhere, but this nuisance is usually caught when the sandwiches are being cut.
Fischler, George. Fountain Pens and Pencils. Schiffer Publishing, Petroski, Henry. Knopf, Thomson, Ruth. Making Pencils. Franklin Watts, Leibson, Beth. July, , p. Lord, Lewis J. January 22, , p. Sprout, Alison. June 15, , p.
0コメント