Drawing Board
The drawing board is an essential tool for learning geometric drawing. Typically crafted from high-quality dry wood, a drawing board consists of several long panels that are closely aligned next to each other, secured by two pieces of wood placed horizontally and firmly.
Advantages of a Drawing Board
The specific design of these boards offers numerous benefits. The surface is characterized by its smoothness and flatness, free from any waviness. Additionally, the edges of the board are required to be perpendicular on all four sides. Made from durable materials, the board often rests on a metal or wooden base, allowing for vertical adjustments or movements upwards and downwards.
The angle of inclination can be adjusted to provide comfort to the artist, preventing fatigue during prolonged use. The drawing board is equipped with various components, including a drawing machine—a device that affixes to the board and can easily move to any point on its surface. This function makes it an excellent substitute for triangles, T-squares, and protractors.
The practice of using geometric perspectives in art dates back to ancient Greek techniques, which were adopted and adapted by Roman painters around the 15th century BC. Artists captured landscapes either directly from nature or through modified interpretations.
Drawing Sheets
Different types of drawing sheets are employed based on the medium used, whether ink or pencil. These sheets often come in cylindrical rolls, categorized according to the desired dimensions.
Specifications of Drawing Sheets
Drawing sheets have distinctive characteristics that set them apart from standard paper, including:
- **Tear Resistance:** The paper should not rip or tear when using a hard pencil or during erasing mistakes.
- **Flexibility Under Bending:** The sheet must retain its integrity without cracking when folded.
- **Durability:** It should withstand the pressure of pencils while drawing.
- **Color Stability:** The paper must maintain its color over time without becoming brittle or weak.
- **Absorption Resistance:** The paper should not absorb ink, preventing spreading and blotting.
- **Moisture Resistance:** The sheets should endure damp conditions and other harsh environmental factors.
Pencils
Pencils are fundamental tools for sketching arcs, lines, polygons, circles, and various other shapes accurately using an appropriate scale. This process is crucial for projecting real measurements clearly onto a drawing sheet.
Types of Pencils and Their Uses
Pencils are categorized based on their hardness into 18 grades, ranging from 9H (the hardest) to 7B (the softest). Each pencil grade serves a specific purpose in geometric drawing according to its softness or firmness. The following table outlines the primary usages of different pencil grades:
| Pencil Grade | Usage |
| HB | Ideal for outlining and marking dimensions in drawings. |
| H | Used for lettering and shape drawing. |
| 2H | Applicable for technical lines such as section lines, dimension lines, hidden lines, and center lines. |
| 3H | Suitable for construction lines. |
T-Square
The T-square is indispensable for drawing horizontal, vertical, parallel, and perpendicular lines, as well as angles and slanted lines in technical drawings. This ruler facilitates accurate line creation according to the required dimensions, thereby clearly conveying fundamental engineering information.
Components of the T-Square and Its Usage
The T-square comprises two parts: the head, which is horizontal, and the body, which is vertical, intersecting at a 90-degree angle. It is typically made from wood or plastic.
To draw with the T-square, the head should be fixed along the edges of the drawing board, allowing the user to move it up and down to achieve the desired height of the lines on the drawing sheet.
Set Squares
Set squares are auxiliary tools in geometric drawing, primarily used for creating 90-degree vertical lines and parallel lines at known angles of 60, 45, or 30 degrees. They are made from transparent plastic, wood, lightweight aluminum, or steel, although the thin, transparent plastic variety is most common.
Types of Set Squares
There are two main types of set squares, each distinguished by their angle compositions: the first type is a triangle with angles of 30-60-90 degrees, and the second type has angles of 45-45-90 degrees.
Crescent Ruler
The crescent ruler consists of various curves and is categorized into different numbered sets to accommodate all drawings that include curves, smooth arcs, or long curved lines that are difficult to achieve with a compass.
Protractor
A protractor is utilized for drawing or measuring various angles. It comprises two components: an upper half-circle graduated from 0 to 180 degrees and a straight lower edge, marked as point O or C to indicate the center of the baseline.
How to Use a Protractor
The protractor is used by placing it on a flat surface such as a T-square, positioning its center over the point from which the slanting line is to be measured or drawn. It can also aid in drawing arcs in technical drawings, typically made from transparent plastic for enhanced visibility of the lines being measured.
Compass
The compass is essential for drawing arcs and circles, as well as for measuring distances, such as those found on maps. It is typically made from metal or plastic and consists of two parts connected by a hinge that adjusts to change the desired radius. One end features a sharp metal point, while the other holds a pencil.
Types of Compasses
Several types of compasses exist, including:
- **Divider Compass:** Primarily used for transferring dimensions and dividing lines without damaging the drawing paper.
- **Spring Compass:** Ideal for drawing arcs and circles.
- **Beam Compass:** Suitable for creating larger circles and arcs.
- **Proportional Compass:** Employed to replicate measurements from reality onto drawings in varying scales.
Geometric Drawing Templates
Geometric drawing templates provide shapes and designs that are difficult to draw with a compass, saving time and effort with ready-made drawings and symbols in various dimensions. These templates vary based on the type of drawings intended, including:
- **Architectural Templates:** For landscapes, windows, or various electrical devices.
- **Circle Templates:** Offering different diameters for circles and arcs.
- **Ellipse Templates**
- **Alphabet Templates**
Manufacturing Geometric Drawing Templates
Geometric drawing templates are made from wood, transparent plastic, or colored materials, greatly facilitating the process of creating engineering drawings. They come in various sizes and shapes, with a preference for those that are easy to clean and feature minimal slipping to ensure stability during usage, thus reducing the risk of errors.