CONICAL CURVES To design shell structures and architectural compositions (Civil Engineering), gear teeth, Todesid other machine components (Mechanical Engineering), a few curves, such as parabola, ellipse, hyperbola, spiral, involute, and cycloids are called for. Parabola, ellipse, and hyperbola are called conic sections they are obtained by cutting a right circular cone by a plane in … Read more
CONSTRUCTION OF REGULAR HEXAGON METHOD -1 (Using Only Compass:) Procedure: With any point O as centre and radius equal to length of the side, draw a circle. With the same radius and starting from any points A on the circle, cut the circle successively at B, C, D, E and F. Connect the sides … Read more
CONSTRUCTION OF REGULAR POLYGON The following procedures describe the methods of drawing regular polygons of any number of sides. METHOD 1: Q.construct a regular polygon of any number of sides (say pentagon) given the length of one of its sides as 25 mm. Solution: Procedure: AB is the given side. It is required to draw … Read more
TO DRAW AN ARC TANGENTIAL TO TWO CIRCLE An arc of given radius may be drawn : (i) Tangential externally to the two given circles, or (ii) Tangential internally to the two given circles, or (iii) Tangential internally to one and externally to the other. TANGENT EXTERNALLY TO BOTH THE CIRCLES Q.Draw an arc of … Read more
TO DRAW AN ARC TANGENT TO A LINE AND PASSING THROUGH A POINT Q. Draw an arc of radius 24 mm passing through a point 18 mm away and tangential to a line 50 mm length. Solution: Procedure: “P” is the point. AB is the line and R is the radius of the arc which … Read more
TO DIVIDE A LINE INTO ANY NUMBER OF EQUAL PARTS Q. Divide a line of 40 mm length into five equal parts and mark on it 3:2; Solution: Let AB be the given line of length 40 mm to be divided into say, five equal parts, Drave a light construction line AC at any converted … Read more
TYPES OF LINES DESCRIPTION OF LINE APPLICATION 1. Continous thick visible out lines and Edges. 2. continous thin ( stright or curve ) Imaginary lines, Dimension lines, Projection lines, Leader lines, Hatching, short centre lines. 3.continous thin (Free hand ) Limits of Partial or interrupted views and sections 4. Continous thin zigzag Long break lines … Read more
DRAWING INSTRUMENTS The drawing instruments which are used to perform drawing work. The different types of drawing instruments mention below. DRAWING BOARD Along the left edge of the board, a groove is cut and a perfectly straight ebony edge called working edge, is inserted into the groove. The drawing board should be placed on the … Read more
IMPORTANCE OF ENGINEERING DRAWING It is a common experience that when we read news papers, magazines, etc. We grasp easily, if it is illustrated with diagrams, sketches, pictures etc. If an attempt is made to describe a machine or a building, much volume of paper is required. But the same could be done easily by … Read more