Technical Drawing

Designing things on paper

Have you ever thought you could make something better, or

come up with an idea to build something new that would be

useful?

When you have a design idea

• Design ideas are what someone develops to solve a problem or to meet a need.

• An example would be; you want to build a better backyard composter, so you research what is composted, how composting works and then come up with an idea of what you would build to accomplish this task.

The next step

• Analyze each/any scenario;

- The idea(s) that you came up with must take into account the materials you have to build it with, as well as the equipment you have to build it, your budget and how much time you have to do it, amongst other things.

- Also remember to meet the goal(s) for which it was designed.

List the resources available

• Write down the things you will need in order to build it;

- Equipment

- Material

For example; What is in or around your home that you can use, can you use things from recycling? What do you need to buy and what will it cost.

Get an idea of how it would look!

• Before you can build your prototype composter you need to draw a design plan.

• Start with a simple sketch

Conceptual Sketches

• When you first get an idea for something you want to build you may draw it roughly, without using instruments or accurate scales. This is called a conceptual sketch.

• A conceptual sketch…– Allows an idea to be

expressed quickly in graphic form

– Is prepared free-hand (without drawing instruments)

– Is not done to scale, but it respects the rules of technical drawing as much as possible, and is made roughly proportional to the object represented.

• A conceptual sketch…– Allows an idea to be

expressed quickly in graphic form

– Is prepared free-hand (without drawing instruments)

– Is not done to scale, but it respects the rules of technical drawing as much as possible, and is made roughly proportional to the object represented.

Draw a design plan. Text P 382

• Next draw a design plan that explains how the prototype works.

• Design plan must include: Any force(s) and the directions of force(s)

• To draw these forces you must use standard symbols. Text p 384

Turn to Text P 382

• Note the standard symbols used in the design plan of the door knob.

• Know the standard symbols p 384 and how to apply them in a design plan!!!!

Next prepare a technical drawing Text P 383

• This is a drawing that shows all the information needed for you or someone to build it.

• What YOU build is a prototype that you will use to test your object, in this case a rocket.

• Results of your testing can result in a redesign or marketing of the object.

Technical Drawings

• Serve as a reference to workers, architects or machinists.

• When you are ready to design the details, you make a technical drawing, done with more detail and more accuracy.

A technical drawing…A technical drawing…

Presents all the information necessary for the object’s construction.Presents all the information necessary for the object’s construction.Is made with great precision, Is made with great precision, Requires the use of rulers, compass and protractor or drafting software.Requires the use of rulers, compass and protractor or drafting software.Is done to scale, and respects the proportions of the object represented.Is done to scale, and respects the proportions of the object represented.Respects conventions in the mode of the representationRespects conventions in the mode of the representation.

Difference:

• Sketch: made without drafting tools... Just pencil and paper. Scale is approximate, not accurate, but the sketch should still look like the object.

• Drawing: made with drafting tools... Ruler, set squares, protractor and compass. Scale should be accurate and the drawing carefully made.

Technical drawings can represent things…

as simple as a spoon,

or…

Technical Drawing of a spoonMulti-view, Orthographic projection

Or A More Complex Technical Drawing of Fighter Plane

(Isometric Projection, exploded view)

Diagrams

• Diagrams are simplified versions of a drawing. Diagrams show how an object works, not necessarily how it looks.

• Diagrams often use abstract symbols rather than actual pictures to represent things.

Diagram of Energy Conversion Unit

– It doesn’t show what the unit looks like, but rather, what it does or how it works.

THE END