Ovals & Elipses

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Ovals and Elipses. From my correspondance it seams that this is a bit of an unknown subject. So first what is the difference, in very basic terms an elipse is a circle but one that is being vewed from an angle to its plane, an oval is however neither, it is just that, an oval. From the point of drawing or developing either of them there is considerable difference, an oval can be drawn using a compass or trammels, an elipse has to be developed which is a whole lot more work. But usually most of us just want an oval, maybe for a badge or emblem and this can be done very simply as follows.....

As in the above diagram draw AB and CD the major and minor axes at right angles to each other, intersecting at O in the centre.

On one half of the major axis describe an equilateral triangle OEA.

On OE mark off P using OC as the length and O as the centre.

Draw a line through C and P intersecting the side of the triangle creating Q.

From Q draw a line parallel to OE creating r and R.

Then R is the centre for the arc CQ, and r is the centre for the arc QA.

It is then just a case of duplication to create the other three sections.

You will find that this works very well for most ovals, for ones with an extreme difference between the major and minor axes it will begin to err.