The Circles are Ellipses in Sketching especially when drawn in Isometric views and 3 Dimensions.
These Ellipses are explained her in the illustration by Nikhil Badde – Design Professor.
The Minor and Major Axis when determined in the isometric square are drawn as shown in the 3 planes here. When the tilt and the angle increases, only the minor axis reduces in length (as shown on the left).
The Measure Axis however is always through the centre of ellipse and tangent to the points where the circles (ellipses) touch the frame squares.
For any further doubts, feel free to write on nikhildesign@gmail.com
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