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Drawing board is one of the main equipment of Draughtsman. It is used for supporting the drawing paper/tracing paper for making drawings. It is made of well seasoned wood strips of about 25 mm thick or masonite, free from knots and warping. It should be softer enough to allow insertion and removal of drawing pins. Two battens are fastened to the board by screws, in slotted joints. They prevent warping and at the same time permit expansion and contraction of the strips due to the change of moisture in the atmosphere.

mini drafter is an important device used for making drawing quickly& accurately. This instrument gives faster drawing as it like the purpose of T Square, Set Square, Protractor and scales.

A mini drafter is an important device used for preparing drawing quickly & accurately. With the use of mini drafter the drawing of building, apartment, industries are planned accurately & too in very less time.

It is of ‘T’ shape, made of well seasoned wood. It has two parts., head and blade. One of thr edge of the blade is the working edge. The blade is screwed to this head such that the working edge is at right angle to head 

The standard ‘T’ square are designated as follows with dimensions shown in mm; as per IS:1360-1989.

The quality of a good drawing does not only depend on the talent of the craftsmen but also on the quality of instruments he uses.

Drawing instruments are generally sold in sets in boxes, but they are also available separately. The main parts of high grade instruments are generally made of nickel or brass. They must be rust proof. Tool steel is used for making the blades of the inking pen, bow instruments and various screws.

It serves the functions of a Tee square, set square, protractor and scale. They come in different sizes and a pattern called ‘Pantagraph’ type. It is fitted on the top left side, edge of the drafting board, mounted on an adjustable frame or table. It requires large area of working place. The angle of the drafting board can be adjusted by pedal operating system. There are two counter weights to balance the angular position of the board and the drafting head. It is more suitable for production drawing office.

Main Types of Engineering Drawing

Engineering drawing is used in all branches of engineering. However, based on major engineering fields, it can be classified into the following types:

1. Mechanical Engineering Drawings:

These drawings are related to machine parts and assemblies used in mechanical engineering.

Technical drawings allows efficient communication among engineers and can be kept as a record of the planning process. Since a picture is worth a thousand words, a technical drawing is a much more effective tool for engineers than a written plan.

Scales: Scales are used to transfer and or to measure the dimensions. They are made of wood, steel, ivory, celluloid or plastic, stainless steel scales are more durable. different types of scales used are shown in Figs 1,2 & 3. They are either flat, bevel edged or triangular cross-section. Scales of 15 cm long, 2 cm wide or 30 cm long 3.5 cm wide flat scales are in general use. Thin section or bevel edged scales are preferred over thick flat scales. Parallax error will be nil or least while using thin / tapered edge scales

Set square (IS:1361-1988): Transparent celluloid /Plastic setsquares are preferred and are commonly used rather ebonite ones. They are two in number, each having one corner with 90°. The setsquare with 60°-30° of 250 mm long and 45° of 200mm long is convenient for use. Setsquares sometimes loose their accuracy due to internal strains. So they should be tested periodically

Sometimes set squares have french curves. Set squares are used to draw all straight lines except horizontal lines. It is convenient to draw horizontal lines using Mini drafter.

Drop spring bow pencil and pen : Drop spring bow pencil and pen are designed for drawing multiple identical small circles. Example: rivet holes, drilled/reamed holes. The central pin is made to move freely up and down through the tube attached to the pen or pencil unit. It is used by holding the knurled head of the tube between thumb and middle finger while the index finger is placed on the top of the pin. The pin point is placed on the centre point of the circle to be drawn and pencil or pen is lowered until it touches paper.