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Wooden pencils are made using a process that dates back to the 1600s. Graphite and clay are mixed to form the lead, which is extruded and superheated. Cedar wood slats are cut and grooved, then glued together with the lead. The sandwich is cut into individual pencils, painted, stamped, and fitted with a ferrule and eraser. Hardness levels indicate how much graphite is released per shot. Pencils used to be fitted with bread erasers until the first erasers were developed in 1770.
Traditional wooden pencils are still made in a process that was first introduced in the 1600s. Modern woodworking machines and automation methods have greatly streamlined the manufacturing process, but most of those made today don’t differ much from their secular predecessors. Essentially, they are the end result of a sandwich process involving graphite and cedar wood slabs.
The first step in making pencils is preparing the graphite core, or “lead.” Graphite is a dark, soft mineral that is ground and added to clay and water in a mixing chamber. After the water has been squeezed out, the remaining graphite/clay compound is allowed to air dry until it becomes a powder again. This graphite powder is mixed once again with water to form a soft paste. The graphite paste is then extruded through thin metal tubes to form pencil-sized rods. These rods are superheated to create hard, smooth leads.
Meanwhile, a woodworking machine cuts the cedar blocks into thinner slats. Another machine cuts eight grooves along the length of these slats. The pencils are not made from a single blank, but actually start out as two half blanks glued together. While the two halves are inserted and glued, another machine places a graphite rod in each of the eight shallow grooves. The entire uncut slab is allowed to dry before further processing.
A special cutting machine receives the uncut sandwiches of wood and graphite, then blades trim the sides to form the familiar hexagonal or round shape. The cutting machine also snaps the plate into individual pencils. Sanders smooth surfaces and prepare them to receive multiple coats of paint. It is not unusual for pencils to receive up to eight coats of varnish to produce the chip-free surface necessary for safe use of the product.
The painted pencils then receive a hot stamp usually containing the manufacturer’s name and a number corresponding to the relative hardness of the graphite lead. The most common hardness has a designation of #2, but those with hardness levels up to #4 are often found at hobby or office supply stores. Hardness generally means how much graphite is released per shot. The higher the hardness number, the less graphite is released, resulting in a clearer line.
The pencils are therefore fitted with a metal collar known as a ferrule. A soft rubber eraser is mechanically inserted into the ferrule and the pencils are now considered complete. Interestingly, the pieces of bread were often used as erasers until the first erasers were developed around the year 1770. It would not be until 1858 that erasers were actually attached to the ends.
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