2. INTRODUCING

3. WHAT IS IT ? SEE SOME EXAMPLES HOW DO YOU DO IT ? EXERCISES

4. ELLIPSE CONSTRUCTION A METHOD OF DRAWING ‘OVALS’ ACCURATELY ellipse construction is... WHAT IS IT ?

5. ELLIPSE CONSTRUCTION LET’S SEE SOME EXAMPLES ellipses Hi-Fi Speaker watch face

6. ELLIPSE CONSTRUCTION HOW DO YOU DO IT ? AUXILIARY CIRCLE METHOD Step 1 - Draw a circle using the major diameter Step 2 - Draw another using the minor diameter Step 3 – Split the circles into 12 equal sections Step 4 – Identify clearly which way round it sits Step 5 – Mark the four points at 3, 6, 9 & 12 o’clock Step 6 – Put in the horizontals and verticals Step 7 – Identify the rest of the points Step 8 – Plot the ellipse by joining up the 12 points You could certainly use a stencil although you would need to have a huge number of them to cover all eventualities.

7. ELLIPSE CONSTRUCTION ALTERNATIVELY... There are some specific advantages with this method – can you think what ? THE TRAMMEL METHOD

8. ELLIPSE CONSTRUCTION EXERCISE 1 CONSTRUCT THE FOLLOWING ELLIPSES A C B D ELLIPSE A Major = 80 Minor = 40 ELLIPSE B Major = 70 Minor = 40 ELLIPSE C Major = 120 Minor = 60 ELLIPSE D Major = 140 Minor = 60

9. FINISHED