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Purpose of studying engineering drawing:

• To develop the ability to produce simple engineering drawing and sketches based on current practice
• To develop the skills to read manufacturing and construction drawings used in industry.
• To develop a working knowledge of the layout of plant and equipment.
• To develop skills in abstracting information from calculation sheets and schematic diagrams to produce working drawings for manufacturers, installers and fabricators.

These are made in many different shapes, normally come in sets of 6,12,16 etc. French curves are best suited to draw smooth curves/ arcs (which cannot be drawn by a compass) with ease. To draw a smooth curve using french curve first set it by trial against a part of the line to be drawn, then shift it to the next portions. Each new portion should fit atleast three points on the curve just drawn. It should be seen that the curve (radius) is increasing or decreasing smoothly and no corner should be formed on the curve

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.

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.

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.

It is used to ink the straight lines drawn with the instruments but never for free hand lines or lettering.

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.

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.

To draw larger circles, it is fitted to the compass. The pencil point or pen point is inserted to its end.

Protractor: Protractor is an instrument for measuring angles. It is semi-circular or circular in shapes and is made of flat celluoid sheet. 

The angles can be set or measured from both sides, aligning the reference line and point ‘0’ with the corner point of the angle.

Figure  shows how to read or set the angle. Protractor can also be used to divide a circle or drawing sectors.