Year 10 Manufacturing (Resistant Materials)

Lesson 2 Week 2 (Clock Project)

Programmes of Study Teachers Rational Lesson1 (Situation and Brief) Practical Skills Design Skills Theory and Knowledge
Lesson 2
Orthographic Drawings
Brainstorming, Cognitive Charts
and Attribute Analysis
Lesson 4
Plastics. Properties, Uses and Common Forms.
Hardwoods and Softwoods Properties, Uses and Common Forms
Ferrous and Non-Ferrous Metals, Properties and Common forms
Drawing Styles and Modelling

lesson 9
Vacuum forming
Lesson 12

The Clock Mechanism
Orthographic Projection (First angle) British
Standards 308

In industry the product is usually made by a different set of people that create the designs. It is important to have a common language. The British Standards Institution recommends ways of displaying information on different types of drawings. These are called
conventions and are understood all over the world.

It is not always possible to draw your design to full size or scale on the page. Sometimes the drawing would be too large to fit onto the page or it would be too small to read the sizes.
Choose a scale and write it on the drawing. A full size drawing is 1:1, a half size drawing is 1:2 and a drawing shown at twice the size is 2:1.

A working drawing needs to show all the dimensions and details needed to manufacture a product (all dimensions must be shown in millimetres).
When producing an orthographic drawing you will generally produce three views. A plan view, end elevation and a front elevation.

The Plan
This is the view looking directly down on top of the object.

The Front Elevation
We are looking straight on at the front of the object. This view normally carries most of the dimensions.

The End Elevation
This is either or sometimes both the remaining side views.

Hidden detail is shown by dotted lines and centre lines are shown by dashed lines. Construction lines are best left in the drawing do not rub them out.
Below is an example of an orthographic drawing in first angle projection.
The drawing has guidelines, centrelines, dimensions and darker finished lines. The drawing of the candlestick holder shows a front elevation, a side elevation and a plan.
The drawing also shows the symbol for first angle projection.


The drawing below shows a clock mechanism that may be placed inside a clock body made in the school workshop. We call the mechanism which is manufactured in large numbers a Standard
Component.( the drawing is not drawn to British Standards 308)

When making a product it is not always necessary to make all the components or parts. Standard components can be easily purchased.

The drawings
opposite shows a side view of the mechanism with the hands and other components about to be attached.

This Exploded drawing will help you to understand how the mechanism works.
Outlines - Thick and Continuous

Projection lines thinner than outlines
Centre Lines, chain lines

Hidden outside and short dashes
Dimension lines, Lighter than outside lines with arrow heads
Cutting plan ;thick at ends with arrows

Break Lines; thin irregular

First Angle Orthographic Projection

Third Angle Orthographic Projection

(Above are all the Convention Lines needed on your drawings)

lesson 2

Either using a drawing package e.g. Microsoft Draw or drawing paper, board and instruments create an Orthographic Drawing of this clock mechanism shown on this page. The drawing must show a front view an end elevation and a plan. The drawing must show correct dimensioning, centre lines and hidden detail lines. The symbol for first angle orthographic drawing must be shown on the drawing.
Create a border around your drawing and in the information block at the bottom display your name, date and the title First Angle Orthographic Projection. Dimensions have been provided on the drawing you may scale these up or down.

Programmes of Study
3h How graphic techniques, I.T equipment and software can be used in a variety of ways to model aspects of design proposals and assist in making decisions;
3h How graphic techniques, I.T equipment and software can be used in a variety of ways to model aspects of design proposals and assist in making decisions;
7.Products and Applications
b The components available for use in the product;