1. COMPUTER AIDED DRAWING
Computer Aided Drawing (CAD) is where we produce our orthographic and 3D drawings using a computer software package. CAD has many advantages and disadvantages over traditional drawing on a drawing board with a pencil. Below is an example of a CAD drawing.
This graphic shows an example of a 3D drawing which was created as a line drawing and then rendered.

2. COMPUTER AIDED DRAWING
ADVANTAGES
Drawings are more Accurate
Ease of modification / edit drawings
Standardisation of drawings
Drawings can be sent over large distances using .
Ability to use a library of commonly used shapes/drawings.

3. COMPUTER AIDED DRAWING
DISADVANTAGES
Initial cost of hardware and software
Need to re-train staff
Computers may crash and drawings are lost
Security of files; files may be hacked
Need to update software

4. COMPUTER AIDED DRAWING
Common CAD Commands
These commands draw arcs, boxes, circles and ellipses quickly and accurately.
Circle
Arc
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Box
Ellipse
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5. COMPUTER AIDED DRAWING
Common CAD Commands
Text
This command allows to add text or writing to a CAD drawing For example adding the labels to views.
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6. COMPUTER AIDED DRAWING
Common CAD Commands
Fillet
The fillet and chamfer are editing commands which allow you to create angled (chamfered) and rounded (filleted) corners.
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Chamfer
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7. COMPUTER AIDED DRAWING
Common CAD Commands
Trim/Break
The trim/break command allows to remove part of a line or object.
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8. COMPUTER AIDED DRAWING
Common CAD Commands
Copy
The copy command allows you to create duplicates of an drawing or image without having to draw the image each time.
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9. COMPUTER AIDED DRAWING
Common CAD Commands
Mirror
axis
The mirror command creates a mirror image copy of an object about a specified axis.
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10. COMPUTER AIDED DRAWING
Common CAD Commands
Zoom/Scale
The zoom/scale command allows the user to reduce or enlarge the size of an object.
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11. COMPUTER AIDED DRAWING
Common CAD Commands
Rectangular Array
The array commands creates multiple copies of an object in circular or rectangular arrangements.
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Polar Array
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12. COMPUTER AIDED DRAWING
Common CAD Commands
Hatch/Pattern Fill
The hatch/pattern fill command inserts a range of line patterns to specified areas within a drawing/object.
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13. COMPUTER AIDED DRAWING
Common CAD Commands
Delete
The delete command as the name suggests, removes a line or selected object.
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14. COMPUTER AIDED DRAWING
Common CAD Commands
rotate
The rotate command allows you to turn an object or drawing through a specified angle.
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15. COMPUTER AIDED DRAWING
TYPICAL EXAM QUESTION