4.20 Textbook of Enginnering Drawing------------------
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A ~-+--------~--------~--~ B
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120
Fig. 4.29 Concetric Circle Method
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- Position the trammel so that the points R and Q lie respectively on the minor and major
axes. As a rule, the third point P will always lie on the ellipse required. - Keeping R on the minor axis and Q on the major axis, move the trammel to Qther position
and locate other points on the curve.
S. Join the points by a smooth curve forming the required ellipse.
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A
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Tramne\ Method
Fig. 4.30 Trammel Method