45^o can be drawn using 45^o Set-square, and 30^o, 60^o can be drawn using 30^o – 60^o Set-square, but to draw 75^o degrees we need both Set-squares. That is only if we keep 30^o of set-square adjacent with 45^o set-square we can get 75^o. And also multiple angles can be achieved using protractor.

The sizes from A0 to A5 decreases, A5 (148 mm x 210 mm), A4 (210 mm x 297 mm), A3 (297 mm x 420 mm), etc. A successive format size is obtained by doubling along width or halving along length.

Bureau of Indian Standards (B.I.S.), American Society of Mechanical Engineering (ASME), American Society for Testing and Materials (ASTM), U.S. National Institute of Standards and Technology (NIST).

Divider is used to transfer dimensions when re is a repetition of dimensions. It is faster method than using a scale and n marking dimension again. Protractors are only used to mark angles and compass is used to draw circles.

In a lengning bar compass, re is a provision for increasing radius of circle greater than total open length of compass. This helps in drawing very large circles with help of medium sized compasses.

French curves are used for drawing curves which cannot be drawn with a compass. Since we are just making a rough sketch of our drawing beforehand, for actual drawing re is no need for French curves. The remaining are primary requirements to sketch any drawing.

6H is hardest grade of lead. The softest grade is 6B. HB is medium soft grade. Generally, for educational purposes, 2HB pencils are used to make drawings. B is soft and H is medium hard. As prefix number increases, softness increases in B and hardness increases in case of H.

A successive format size (from A0 to A5) is obtained by halving along length or doubling along width. So areas of two subsequent sizes are in ratio 1:2. Likewise in reverse order (from A5 to A0), ratio will be 2:1.

Mini ? drafters are used to draw perpendicular lines, parallel lines and angular lines. They consist of blades, protractor head, double bar link mechanism, screw and clamp. The blades have markings corresponding to engineering scale.

The sheet may be placed in any direction but within sheet, drawing should be specified particularly for reproduction purpose, main purpose is to facilitate positioning of drawing and parts in it.