Pencils

Make: Traditional pencils are made from special wood with lead of compressed clay and graphite. They are widely available in 19 graphite grades, ranging from very hard (containing more clay) to very soft and dark (containing more graphite)

Grade HB is regarded as the most versatile for general drawing and sketching. Commonly used are H, F, HB and B especially for beginners for setting out line, fine work and rough sketch on cartridge papers. The degree of hardness or softness is always indicated near the end of the pencil or lead and varies from manufacturer to manufacturer.

Shape (section): The standard length of a traditional wooden pencil is 175mm. Common cross-sections are

-          Hexagonal

-          Circular

-          Triangular

The hexagonal cross-section is more common as it is easy to hold and does not roll of the board or table.

Importance

-          It is the most responsive and versatile of all drawing media.

-          At the onset of design, pencils are commonly employed to respond to the sensitive externalization of new concept (ideas) which hitherto were experienced only in the mind’s eye.

-          Pencils are ideal for rapid free-hand sketching and final presentation of design.

-          Pencils lead offers a wide range of line weights and types depending on graphite grades, paper texture and degree of pressure and pencil.

Factors affecting selection of Lead

1.       Quality of drawing paper i.e. degree of tooth or roughness: The more tooth a paper has, the harder the lead to be used

2.       The drawing surface: The harder the surface, the softer the pencil and vice versa.

3.       Weather conditions e.g. temperature and humidity affect performance of lead chosen. High humidity conditions tend to increase apparent hardness of the length.

4.       Accuracy of the required drawing

5.       Standard required for reproduction

6.       Pressure to be exerted by the user

Disadvantages of the Pencil

One main disadvantage of the wooden pencil is that through sharpening, its original length is reduced and its balance destroyed as it becomes difficult to hold by the fingers.

The Clutch Pencil

This is a more sophisticated alternative to the traditional wooden pencil. It is of similar shape and size to the wooden pencil. It consists of a plastic or metal lead holder, into which a .2mm leads of varying grades or colours can be inserted. A push button operates the clutch and enables the lead to be withdrawn or fully projected as required.

Advantages

-          Its main advantage is that the balance(length) is always constant

-          It is also heavier

-          The lead pointer is incorporated into the push button

Fine Lead Clutch Pencils

They are also push button drawing instruments; the fine leads are also available in 6 degrees of hardness. They offer a consistent line quality. The leads are so fine that they need no sharpening, but they are not recommended for sketching as they snap under pressure.

Ebony, Carbon and Carpenter’s Pencil

They contain thick soft black leads which are ideal for large expressive drawings such as trial perspectives and atmospheric sketches. Their crayon-like boldness relates more to freedom and weakness of thought than precision drawings. The carpenter’s pencil stands out because of its wedge point.

Sharpening the Pencil

Pencils are sharpened to achieve the pointing shape of lead. There are three kinds of points

-          Normal

-          Needle or Drafting

-          Wedge

Points can be hard sharpened using the sharp lead or with mechanical or electrical operated sharpening machines or clutch pencils. The sharpener could be portable or bench mounted. Clutch lead holders often incorporate a detachable lead pointer. More efficient is the .2mm lead pointer. Wood and clutch pencil points can be maintained using sand paper blocks. Points can also be retained while drawing by continually rotating the pencil between the fore-finger and the thumb at an angle of 45⁰.