Thursday, August 15, 2013

How are Pencils Made

You may be surprised to know that the manufacturing process of the traditional wooden pencils are still the same as that followed during the 1600s, when this writing device was introduced for the first time. The only difference is that now sophisticated machines are being used for this purpose instead of the traditional ones. The history of pencils can be traced back to the period of ancient Egyptians and Romans, who used a crude form of pencil called 'stylus', which were thin metal sticks made of lead. These sticks were used to make marks on 'papyrus', an early version of paper. The word pencil is derived from the Latin word pencillus, which means 'little tail'.

History of Pencils

The origin of pencils can be traced back to the early 15th century. The use of graphite in pencils started with the discovery of a graphite mine in England, during the 1500s. Soon, people started using it for marking sheep, as the graphite was so pure and solid, that it was very easy to cut it into sticks. Later, they realized that the graphite sticks required some sort of case to make it stable. They used strings or sheepskin to cover the sticks. Eventually, these cases were replaced by wooden ones, which are still being used worldwide. It was the Germans who, in 1662, introduced the method of using a mixture of graphite powder in pencils. Pencils have traveled a long way from the crude form used in the 1600s to the modern-day mechanical ones. Contrary to conventional wooden pencils, these mechanical pencils lack the wooden case. The lead of this pencil is not attached to the case. Its mechanism makes it possible to extend the lead, as the tip of the pencil is worn away.

How are Pencils Made

Even though the inner core of the pencils are made of graphite, people still call it lead. In reality, there is no trace of lead in pencils. The outer case of a conventional pencil is made of wood and the inner core consists of a mixture of graphite and clay. The inner core can also be made of colored pigments (to make color pencils) or charcoal too.
  • The primary task is to make the core of the pencil, which is known as 'lead'. Graphite, which is a soft mineral, is ground and is mixed with clay and water. This mixing process takes place in a mixing chamber, where the water is removed after the process. Then, the mixture is air dried to form a powder. This powder is again mixed with water to produce a soft paste, which is fed into thin metal tubes and extruded in the form of thin rods, to form the core of pencils. These rods are superheated to form hard and smooth pencil leads.
  • The conventional wood pencils require a wooden case, which is usually made of cedar wood but can be made from different types of wood. Cedar logs, which are cut into pencil stock, are transported to the slat factory, where thin slats are made with the help of a circular saw. These slats are sorted as per the width and grain and are stained, before transporting them to the pencil factory.
  • In the pencil factory, eight shallow grooves are cut into one side of the slat and graphite cores are placed into the grooves. Each groove is fitted with one of the leads prepared earlier.
  • In the next step, the grooved slat, fitted with graphite cores, are glued with another grooved slat. Both slats are glued in such a manner that the grooves overlap each other, to form a tube-like structure, which contains the graphite core.
  • The slats are clamped together till the glue dries and then are sent for the milling process, which separates individual pencils by cutting the slat. This is followed by the trimming process, which is employed to trim the pencils to a uniform length. After this process, the pencils are given the desired shape. It can be round, triangular or hexagonal.
  • Next is the turn of sanding machines to make the surface of the pencils smooth and make them ready for painting. These pencils are coated with several coats of paint or lacquer. Normally, eight to ten coats are applied over the surface of a pencil to make the surface more smooth and splinter free.
  • If the pencil is supposed to be attached with an eraser, a depression is made in one end, to attach the ferrule. A ferrule is a metal ring, which holds the eraser. A special machine is employed to attach the ferrule and the eraser to the pencil. The next step is the imprinting of the brand name, by hot stamping on the surface. The number corresponding to the relative hardness (for example, 2 HB) of the lead is also stamped. The last step involves the packing of pencils for distribution.
The manufacture of pencils involves the use of natural resources like wood, clay, graphite and water. It also requires electricity and manpower. So, wasting of pencils is like wasting our resources and the efforts of the people involved in it.

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