How to draw ellipse with compass

Many people think that the oval and the ellipse is the same shape. They are absolutely wrong - although outwardly both figures have large similarities in geometry, it's a completely different shape. Easy oval, you can easily draw using only one caliper, but the right ellipse requires not only a compassbut also a certain knowledge of the build of this figure.

You will need

a compass, ruler, pencil, Kripke thread and 3 pins.

Instruction

The first method. Take a ruler and pencil. Draw two straight, perpendicular to each other.

Take a compass and putting it in the point of intersection of lines, draw a small circle. This is the width of the ellipseor in other words the width of the minor axis. Draw, without removing the compasses from the point of intersection of the perpendicular lines, great circle. The diameter of this circle is equal to the length of the ellipsethat is the major axis.

Divide into twelve equal parts of a greater circle. Connect them with lines that go through the center of the dividing point and opposite each other. Separating great circle itself you should be divided into 12 parts and smaller.

Find the highest point in the circle and put near it the number 1. Number of units in a clockwise direction. Draw from all the points of the larger circle (except 1, 4, 7, 10) vertical lines down.

Swipe of corresponding points that are on the small circumference, the horizontal lines so that they intersect with the vertical. So, for example, a vertical line from point 2 of the larger circle will intersect with the horizontal line under the number 2 small circumference. Connect all the points of intersection of the horizontal and vertical lines, including points 1, 4, 7, 10 are drawn small circles, using a smooth curve. Erase unnecessary lines. The ellipse is constructed.

The second method. Prepare a compass, a ruler, a pencil, strong linen thread and 3 pins. Draw a simple rectangle using a ruler and pencil. The length and width of the rectangle should equal the height and width of the ellipse.

Divide by two intersecting lines of the rectangle into four equal parts. Take a compass and draw a circle that will intersect the long middle line. To draw such a circle, you need to install compass, or rather his rod into the center of one side of your rectangle. The radius of the circle this will set the length of the sides of the rectangle, respectively, divided by two.

Mark on the pattern of the points where the circle crosses the vertical midline. Plug in the data points of the pins. You can use a simple pushpin with a big stinger. Insert the third pin (button) to the end of the middle line. Tie with linen thread all three pins.

Remove the third pin and instead, insert the string a pencil. Draw the curve, pulling on the thread evenly around the perimeter. Erase unnecessary lines. The ellipse is ready.

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