Textbook of Engineering Drawing, Second Edition

(Jacob Rumans) #1

--------------------'---Geometrical Contructions 4.7


Fig. 4.11


  1. Join B to second division

  2. Irrespective of the number of sides of the polygon B is always joined to the second
    division.

  3. Draw the perpendicular bisectors of AB and B2 to intersect at O.

  4. Draw a circle with 0 as centre and OB as radius.

  5. WithAB as radius intersect the circle successively at D and E. Thenjoin CD. DE and EA.

  6. To construct a regular polygon (say a hexagon) given the side AB -alternate
    method.
    construction (Fig.4.12)


E

F

A B

Fig. 4.12


  1. Steps 1 to 3 are same as above

  2. Join B-3, B-4, B-5 and produce them.

  3. With 2 as centre and radius AB intersect the line B, 3 produced at D. Similarly get the
    point E and F.

  4. Join 2-D, D-E, E-F and F-A to get the required hexagon.

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