How to Draw an Oval With String

The word "oval" comes from the Latin word for egg.

An oval is a shape that resembles an egg or a rounded rectangle. According to the Wolfram Math World website, an oval does not have an exact mathematical definition. The word "oval" comes from "ovus," the Latin word for egg. One method for drawing an oval with a string is to use two pins and a compass. Start by deciding on the width and height of the oval you want to draw, then create a major axis and a minor axis. It's a bit tricky the first time, but once you figure it out, it's easy.

Things You'll Need

• Ruler
• Pencil
• Compass
• 2 pins
• String

Instructions

1. Draw a straight line representing the overall length of your oval. This is your major axis.

2. Mark the midpoint of your major axis. At the midpoint, draw a perpendicular line that represents the width of your oval. This is your minor axis. The major axis and the minor axis should intersect at a 90-degree angle to form a cross.

3. Place the point of your compass on the spot where the two lines intersect. Adjust the pencil on the compass so it touches one end of the major axis. Leave the compass adjusted to that width.

4. Place the point of the compass on one end of the minor axis. Use the compass to draw two short arcs across the major axis -- one on the right side and one on the left side. The points where the arcs cross the major axis are called the foci. Label one F1 and the other F2.

5. Push a pin into one endpoint of the major axis. Push another pin into the other endpoint of the major axis. Tie a string between the two pins. Be sure the string is taut.

6. Pull the pins out carefully and, without removing the string, move the pins inward toward the center of your drawing. Push one pin into the paper at F1. Push the other pin into the paper at F2. Do not change the length of the string. The slack string will guide you in drawing the oval.

7. Place a pencil inside the loop of string and gently pull it taut. Put your pencil at one endpoint of the major axis. Keep even tension on the string as you draw an arc toward the endpoint of the minor axis. The line you create will be the first quarter of your oval. Continue drawing toward the other endpoint of the major axis, and you will have completed half of your oval.

8. Move your pencil to the other side of the string, pull it taut, and repeat the procedure to draw the other half of the oval.

Tips & Warnings

• Before beginning, set your paper over a cork board or other surface that you can stick pins into. This will keep the pins in place while you work and prevent damage to the surface under your paper.

References

• Math Open Reference: Draw an Ellipse Using String and 2 Pins
• A Woodworker's Bench Notes: Laying Out An Ellipse
• Wolfram Math World; Oval, Eric W.Weisstein

Resources

• Kidipede: Area of an Oval