When it comes to pencils, #2s are just in the center of the pack. Pencils with a number greater than two have harder leads and are frequently used by engineers, architects, and draftsmen due to their harsher tips. The basic rationale here is that the more difficult point provides the user more control over the lead. A two-lead pencil can be used for fine detail work where the softer tip is desirable.
Number one pencils are special edition pencils that are sometimes called "signature" or "limited edition" pencils. These are the most popular type of pencil among students because they are cheap and easy to find. They usually cost $1.50 to $3.00 each and come in colors such as red, blue, yellow, and white. Signature pencils were originally produced by simply numbering each tube of wood that made up the pencil. Today, some manufacturers produce signature pencils that use special materials such as graphite or clay instead. Either way, these pencils are unique because each one is individually numbered. There may also be writing or pictures on the pencil box or barrel tag attached to the pencil itself.
So, number one pencils are basically regular old pencils that you can buy at any school supply store. They usually cost around $1.50 to $3.00 each. Number two pencils are harder leads and are commonly used by engineers, architects, and drafters due to their harsher tips.
On the rest of the world's scale, an American #2 pencil (approximately) equates to an HB pencil. The lead is neither too black nor too light, not too firm nor too soft. Number 2 pencils are common school tools that are easy to obtain and inexpensive.
Harder pencil leads begin with 2H, which is comparable to a number 4 in the US numbering system, then progress to 3H, 4H, and so on. The HB grade lead is the hardest.
The hardness of graphite varies depending on its source. Generally, it gets harder as it goes further into the earth's core - deep-sea or ice-core graphite is hard enough to cut glass, for example. Broomstick (or bamboo) graphite is the hardest, followed by longhorn (or maple) graphite. The softest types of available lead are 2B and 2C.
When you ask for a harder lead, people usually mean a hickory stick or charcoal briquette. These materials are extremely hard, but not that different from each other in terms of their surface texture. A harder lead will produce darker marks with less smearing. It will also be more flexible than a softer lead.
People used to make their own leaded pencils by mixing natural materials such as bark or wood with clay to make moldable shapes that they would burnish with another shape of clay until the desired thickness was reached. This process was labor intensive and only really suitable for small quantities. In 1872, Charles Dixon invented the first factory method for making lead pencil shells.
Lower-numbered pencils have softer graphite and so make deeper lines; they are commonly used by people in the publishing sector. Pencils with a number less than 2 are made of tougher graphite and produce lighter marks when used. These are suitable for general use.
Number 2 pencils can be split into two types: standard and HB. The name "standard" comes from the fact that these pencils usually have a diameter of 2 1/4 inches (5.7 cm). They are good for general writing purposes. HB stands for hardboard, because the lead container is made of hardboard.
Pencils with a number greater than 2 are called technical or mechanical pencils. These are very popular with artists because they allow them to make quick, precise sketches with ease. Technical pencils come in various sizes and styles. But most often they are either silver or black.
Technical pencils contain a small metal barrel inside the casing of the pen unit where the lead is stored.
Higher numbers denote a harder lead, which produces a sharper point and clearer lines. Lower values imply a softer lead, which is ideal for shading. #2 is the Goldilocks of pencils: not too firm, not too soft, and suitable for almost all of your requirements.
The name "2-Bolster" comes from the fact that these leads have two flat surfaces on one side, which are used to hold the lead straight while writing. The term "bolster" came into use in the United States during the 1940s. Previously, these leads were called "square" or "flat" leads.
Number 2 pencils were first manufactured by the Faber-Castell company in 1881. They introduced several improvements throughout their early years, such as shorter handles for younger students who might be unable to grip the pencill long enough to use it properly. In 1930, they developed a new type of lead called "HB", which means "hardboard". This lead is made of compressed wood fibers that provide more strength than conventional charcoal pencil leads.
In 1955, the No. 2 pencil was given its own category at the Chicago World's Fair. These leads are still available today, although they are being replaced by lower-number leads (6, 7, and 1) in many countries because they can be bought in any quantity without having to specify a number value.