pEnciL fActs

An interesting article, think I should post it here.

Have you ever wondered how does the lead get into the pencil?

A solution of finely ground graphite, clay, and water is forced through a narrow metal tube and comes out looking like a long string of spaghetti. After being dried, cut, and fired in a kiln, the lead is immersed in hot oil and wax. The wood, usually cedar, which is easily sharpened, is sawed into slats-planned and grooved pieces of wood-half a pencil thick. The leads are inserted into the grooves on one slat, and a second slat is glued and pressed on top of the first. When the glue dries, the individual pencil are cut apart. After shaping, sandpapering, painting, and stamping with the manufacturer's trademark and other details, the now seemless pencil is ready for use. Sometimes an eraser is attached to one end.

Which pencil should I use?

To select the pencil you need, note the letters or numbers printed on the side of the pencil. These indicates the degree of hardness or softness. Softer lead leave a darker mark.

HB is a versatile, medium-grade lead.
B denotes softer leads. A number such as 2B or 6B denotes the degree of softness-the higher the number, the softer the lead.
H denotes harder leads. The higher the number-2H, 4H, 6H, and so on-the harder the lead.
F stands for fine point.