Page 89 - CITS - ED - Mechanical

ENGINEERING DRAWING - CITS

• Draw the isometric view of the hexagonal base a b c d e f of the prism using offset method.
1 1 1 1 1 1
• Draw the top hexagonal face by drawing projection from the corners of the base.
• Make the visible edges by drawing thick lines and draw the invisible edges in hidden line.
• Rub off the unwanted lines and complete the isometric projection.
• Use isometric scale of all measurements.

Fig 26

Exercise 5.27

Draw the isometric views of a hexagonal pyramid of side base 30 mm and height 75 mm given its position as under:
• its base resting on HP and the edge of the base parallel to VP. (Fig 27)
• Draw the plan and elevation of the pyramid (true scale) and enclose the plan in the rectangle PQRS. (Fig 27a)

• Draw the parallelogram with two of its adjacent edges at 30° to the horizontal. (Fig 27b) PQ = Isometric length
of pq and PS = Isometric length of PS.
• Draw an isometric hexagon ABCDEF in the parallelogram PQRS. (Fig 27b)

• Mark the centre `O' and draw a vertical line from point `O' of height to 75 mm in isometric scale.
• Join `O', with ABCDE&F to complete the required isometric projection of the hexagonal pyramid. (Fig 27c)

Fig 27

Exercise 5.28
A sphere positioned at the centre of the top face of a square prism as shown in Fig 28. Draw the isometric projection.
• Draw the isometric projection of the square prism. (Fig 28a)
• Mark the mid points of the sides. Join the mid points and locate centre `O'.

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CITS : Engineering Drawing (Mechanical) - Exercise 5