The 3D graphic on the right shows a headrest for a sports car - Leaving Cert DCG - Question C-3 - 2014

After establishing the outline, fill in any internal features seen in the figure, ensuring that the contours and curves of the headrest are accurately depicted. Include the lower edge of 10 mm and 20 mm allocation as shown.

Illustrate the end elevation by representing the side profile of the headrest, incorporating the height and curve as established earlier. Verify that the projection meets the outlined top contour accurately.

To accurately finish the end elevation, locate the center of the headrest shape, which is crucial for symmetry. Then draw the curved outline to match the R40 radius indicated, ensuring a smooth transition from the straight edges to the curved areas. This part is essential for the aesthetic and functional aspects of the headrest.

To create the surface development, start with the back of the headrest. It can be approximated as a flat surface with the height and width copied from the elevation view.

From the back surface, unfold the top surface based on its width of 75 mm and account for the rounded edge, incorporating it into the development.

Each side of the headrest should be developed into a flat plane, measuring the total height from the top surface down to the base and the contour along the R40 curvature.

The under surface will mirror the back surface in width while keeping the height consistent. Include the straight segments and any curvature transitions.

The front vertical surface develops as a straight piece that connects the top and bottom surfaces, presenting the exposed edge of the headrest.

This section divides the curved surface into manageable sections for realistic material cutting. Practically, you can use radial lines based on the R40 curve to divide it into equal segments.

The development of the curved surface will be a series of a few small trapezoidal shapes that overlap slightly, providing a flexible surface for material deployment.

Ensure that your drawings are clean, with consistent line weights and labels for each section of the development. Clear differentiations between folded and flat areas will enhance understanding and presentation quality.