How are pencils made?

How are pencils made? If you examine the writing end of a brand-new pencil before sharpening it, you might think that the wood casing is one continuous piece. This could lead you to assume that pencil manufacturers simply drill a hole down the center of the wood and insert a lead rod. While early pencil creators worked this way, modern mass production methods are quite different.

Is It Really Lead?

Before diving into how the lead is inserted into the wooden casing, let's clarify what the 'lead' actually is. The substance commonly referred to as lead in pencils isn't lead at all. Instead, it's a mixture of powdered graphite and clay, combined with water and then pressed into thin rods under high heat.

The term 'lead' originated because the Englishmen who first discovered graphite mistakenly thought they had found lead. According to the Cumberland Pencil Museum, a fierce storm in the mid-16th century in Borrowdale, England, toppled several trees, revealing a large deposit of a black substance initially believed to be lead.

Over 200 years later, an English scientist determined that the substance was not lead, but rather a form of carbon. It was named graphite, derived from the Greek word 'graphite,' meaning 'to write,' as it was primarily used for writing.

A Brief History of Pencil Shapes and Designs

In the early days of pencil making, graphite pencils were crude versions of the more refined pencils professionals use today. The first pencil was merely a block of graphite that carpenters and artisans used for marking materials without damaging them.

Pencil making techniques evolved rapidly. A craftsman eventually designed a new writing tool by wrapping a chunk of graphite in sheepskin. This was followed by the invention of a string-wrapped graphite pencil, the first to feature a rod-shaped graphite core. Writers had to unwind the string as the graphite wore down.

The next significant innovation in pencil design involved hollowing out a cedar stick and inserting graphite sticks into the cavity, a method often attributed to the Italians. The English adopted this approach but streamlined the manufacturing process considerably.

Rather than hollowing out a whole piece of wood, the English simply carved a groove in the wood, inserted a piece of graphite, and then broke it off flush with the top of the groove. A small wooden slat was glued on top, encasing the graphite.

Touring a Modern Pencil Factory

The pencil production process has evolved greatly over time. Today, most wooden pencils are mass-produced from large blocks of cedar, which are sliced into slats. A machine carves eight grooves, half the depth of the graphite-clay rod, into the slats before placing the rods into each groove. A second grooved slat is then glued on top to enclose the graphite.

Once the glue has dried, the slats pass through a cutting machine that shapes the wood into various forms and separates the slats into eight individual pencils. The seams where the two slats meet are sanded down, and several layers of paint are applied to create the appearance of a solid pencil.

According to Musgrave Pencil Co. Inc, over 14 billion pencils are produced annually worldwide—enough to wrap around the Earth 62 times. This vast quantity includes a wide range of styles and sizes. If you've ever filled out a bubble test, you're likely aware that pencils vary in terms of darkness.

The number printed on the pencil represents the hardness and darkness of the graphite core: the higher the number, the harder the graphite. A harder core leaves behind less graphite-clay mixture on the paper, resulting in a lighter mark compared to a softer core.

A Bit About Coloring Pencils

While the story of the traditional pencil is intriguing, we must also appreciate its colorful counterparts: colored pencils. A popular tool among artists, illustrators, and children, these pencils bring color to our otherwise black-and-white graphite world.

As early as the 19th century, artists were in search of a portable and precise coloring tool. They experimented with wax-based crayons and oil pastels, but longed for something that offered more control. This led to the creation of the coloring pencil.

Unlike the standard pencil, which uses a graphite-clay blend for its core, coloring pencils are filled with a mixture of pigments, binders, and fillers. The binder, usually made of wax or oil, holds the pigment together and gives the pencil its smooth consistency.