Page 120 - CITS - ED - Mechanical

ENGINEERING DRAWING - CITS

• Draw the plan and front view of the truncated cylinder.
• Divide the circle into any number of equal parts.
• Project these points to the front view to form the elements of surface of the cylinder.
• Assuming the cylinder as a whole draw the full development of the cylinder.

• Draw the length of the development also divide into 12 equal parts as in the plan.
• Project the true height of the each elements to cut the development of the cylinder.
• Join all the points by a smooth curve to obtain the required development.

Exercise 7.9
Draw the development of the lateral surface of the cone as positioned. (Fig 9)

Fig 9

• Draw the views of the cone and cutting plane on it.
• Divide the base into any number of equal parts, say 12 and mark them.
• Project the points on to FV and join to the apex.
• Mark the points on the cutting plane and draw lines parallel to base, touching the generator at 1 ,2 ....7 . These
1
1
1
are the true lengths from 0'.
• Draw the sector with slope as radius.
Radius of cone
Sector angle θ = length (S) x360
= Slope
25 X360 121
74.33

• Mark O and set angle θ.
1
• Transfer the true lengths on the cone on to the sectors and join by smooth curve.
The area between this curve and the arc is the development of the lateral surface.

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CITS : Engineering Drawing (Mechanical) - Exercise 7