Introduction: Drawing Ellipses
Here is an easy way to draw an ellipse by hand with a few basic materials.
Step 1: Materials
For this project you will need some string or yarn, two push pins, a writing utensil, and a some surface to draw on.
Step 2: Tie String
Now, take your piece of string and tie the two ends together so that it makes a big circle. The length of your string determines how big the ellipse will be. For a good estimate, half the length of the string will be a little bit more than the minor axis of your ellipse, depending on how elliptical your ellipse is.
Step 3: Draw
Next, push the pins in your drawing surface (a few inches apart) and put the string around them. Then, put the pencil at a third point on the string and pull outward as you draw around. An ellipsed should be formed.
The farther apart your pins are, the narrower the ellipse will be. The closer the pins are, the more the ellipse will resemble a circle.
21 Discussions
13 years ago on Introduction
Awesome. Isn't this closely related to Kepler's three laws?
Reply 1 year ago
no. the pins positions are at ellipses foci. the foci of an ellipse are two fundamentals of the ellipse
9 years ago on Introduction
Thank you! I use such shapes for creating sets for the Nature Center, in this case, an oval to paint pocupines inside of...as part of a title display panel! I needed a LARGE one, since they are over 6 feel high and 3 feel wide.:)
Knew it would be simple, but, was not quite sure..so thank you!
cheers.
9 years ago on Introduction
Let's see...
To answer 3/4 of the comments on here:
http://lmgtfy.com/?q=ellipse
10 years ago on Introduction
An excellent technique, and very useful - if you ever need to cut a hole to pass a vertical pipe (chimney, flue, drain etc) through a sloping roof then the shape you need is an ellipse.
12 years ago on Introduction
excellent been racking my brains and this oh so simple solution ,does the business
13 years ago on Introduction
A common sense solution. (because an ellipse is defined as a set of points in which the sum of the distances between two foci is constant) I like it. In a similar vein, using only one focus, the result is a circle. Using three or more (noncollinear) foci could yield interesting shapes, which could be useful for making signs or templates.
14 years ago
That's quite clever. Now I'll need to think of a good reason to draw an ellipse :)
Reply 14 years ago
ellipseseses can be handy when you need to cut an arc out of something, as opposed to a simple quadrant from a circle. Like a fancy schmanky coffee table corner or sumfink.
Reply 14 years ago
What´s a schmanky coffee table like ?
Reply 14 years ago
I kindly direct your attention to the attached object of fancy schmankyness (including ovalesque corner cuttouts)
Reply 14 years ago
Woooshh !!
Reply 14 years ago
*nods* Good point.
How about a custommini CD in the shape of an ellipse? That would be cool.
14 years ago
I once tried pulling out one of my hairs to use as the string to do this in an exercise book. School was really boring.
14 years ago
what is an Ellipse
Reply 14 years ago
It's the maths way of saying "oval".
14 years ago
Distance between pins:
2 x Sq root of {(1/2L)squared minus(1/2H)squared}, where L=lenght and H=height of final ellipse.
Reply 14 years ago
Clever you. Can you now tell me how to find the largest circle I can inscribe in a given ellipse ? I can't :)
Reply 14 years ago
Simple. The center is midway between the two points (push pins). The radius equals the height of the ellipse (distance to nearest edge).
14 years ago
If it is to be inscribed, diameter should be equal to the ellipse´s height (y axis).