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STRUCTURE OF PRESENTATION
• Introduction
• Tools for Drawing
• Paper sizes
• Title Block
• Dimensioning
• Lettering
• Lines
WHY ENGINEERING DRAWING?
• A drawing is a graphic representation of an object,
or a part of it, and is the result of creative thought
by an engineer or technician.
• Engineering Drawing is a formal and precise way of
communicating information about the shape, size,
features and precision of physical objects.
• Drawing is the universal language of engineering.
Engineering drawing ENGN103 Introduction: Overview
DRAWING TOOLS
• To prepare a drawing, one can use: • Manual drafting instruments • Computer-aided drafting or design, or CAD.
• The basic drawing standards and conventions are the same regardless
of what design tool you use to make the drawings.
• In learning drafting, we will approach it from the perspective of manual drafting.
• If the drawing is made without either instruments or CAD, it is called a freehand sketch.
Engineering drawing ENGN103 Introduction: Apparatus
T-SCALE
Engineering drawing ENGN103 Introduction: Apparatus
TRIANGLE / SET-SQUARE
Engineering drawing ENGN103 Introduction: Apparatus
Adjustable Triangle Set-square: 30 & 60, 45
• Thick- HB grade pencil
• Medium- H Grade
pencil
• Thin- 4H grade pencil
Engineering drawing ENGN103 Introduction: Lines-Home Work
DRAWING SCALE
• The ratio of the length in a drawing (or model) to
the length of the real thing. 1: 10, 1:1, 1:200 etc
Example: in the drawing anything with the size of "1" would have a size of "10" in the real world, so a measurement of 150mm on the drawing would be 1500mm on the real horse.
• A drawing that shows a real object with accurate
sizes except they have all been reduced or
enlarged by a certain amount (called the scale)is a
scale drawing.
SCALE • When the object is bigger than the size of drawing sheet, it is drawn
at reduced scale.
• Therefore, scale is the ration of actual object and the size shown on
the drawing. The scales are designated as:
• SCALE 1: X for reduced scale (X is the ratio)
• SCALE X:1 for enlarged scale
• SCALE 1:1 for full size
• Standard recommended ratios are multiples of 2, 5 and 10 as:
• Enlargement: 50:1, 20:1, 10:1, 5:1, 2:1
• Reduction: 1:2, 1:10, 1:20, 1:50, 1:100, 1:200, 1:500, 1:1000, 1:2000,
1:5000