A mechanical pencil is an instrument that uses erasable lead rods for drawing, writing texts and designing on mediums like paper and wood. It is commonly used in drawing and writing texts on paper. The pencil is made up of high impact plastic and wrapped with a soft rubber for comfort gripping while writing or drawing.
The pencil consists of two parts as seen below namely:
- A gripping assembly
- Barrel assembly
Gripping assembly
This is a hollow rubber and chrome casing that is designed to protect the internal features and hold the lead rods. The rubber casing is for finger gripping during writing. The barrel measures 2.5 inch in length and 0.5 inch in diameter. This gripping assembly is attached to the barrel assembly, and has three main parts namely:
- Rubber gripping barrel
- Cone cap
- Lead road outlet
Barrel assembly
This is a hollow casing designed mainly to hold the lead rods and eraser. It is fitted with a chrome pocket, clamp holder. It is attached to the gripping barrel and helps in the balancing of the mechanical pencil during writing as it rests in the index finger. It measures 2.75 inches in length and 0.5 inches in diameter. It is composed of four main parts namely:
- Hourglass barrel
- Pocket clamp holder
- Lead rod ejector
- Removable eraser
The diagram is as below.
The mechanical pencil is an instrument that is easy to use and maintain. Its physical features are those of a pen. It has a lead rod but does not have the limitations of the normal lead and wood pencil. The pencil is available at retail outlets such as art and craft stores and those stores that supply such related items.
It’s Operation
When writing with the mechanical pencil, one has to make sure that at least one lead rod is loaded into the hollow barrel. The eraser can be removed and the worn down erasers replaced by new ones. The eraser is used to eject the lead rods out of its outlet by pressing it down using a thumb as shown in the picture below.
The mechanical pencil can hold by either left or right hand. A symbol is drawn on a piece of writing material by moving of the pencil to a desired direction. A little pressure between the piece of paper and the lead rod is applied.
The mechanical pencil can last for long since the lead rods can be purchased separately, making it advantageous over the traditional lead and wood pencil. The pencil does not need to be sharpened and never decreases in size as the traditional lead and wood pencil. The rubber-gripping barrel prevents a build up of callus under middle finger joint when used for long periods.