CHAPTER 2
Introduction to Manual Drawing
2
ad
zly a
nuar
© 2
00
1-2
00
4
Contents
• Drawing tools
• Drawing sheets and layout
• Lettering
• Lines
• Scale
• Abbreviations
MEMB113 | MANUAL DRAWING | CHAPTER 2
4
ad
zly a
nuar
© 2
00
1-2
00
4
2.1 Drawing tools
• Tools and instruments that are used to produce technical drawing manually
• Some tools are essentials while others are optional
• Including:– The drawing board/table– Drawing instruments– Measuring instruments– The set squares– Pencils and erasers– Instruments to aid the drawing of curves
MEMB113 | MANUAL DRAWING | CHAPTER 2
5
ad
zly a
nuar
© 2
00
1-2
00
4
2.1 Drawing tools
• These are used to place the paper for drawing
• The drawing table– Normally A0 or A1 size– Usually attached with Tee-
square
• The drawing board– Normally a flat wooden board
with Tee square– Size to suit the range of paper
sizes (A0-A3)– Drawing sheet is fixed to the
board using clips or tape
MEMB113 | MANUAL DRAWING | CHAPTER 2
6
ad
zly a
nuar
© 2
00
1-2
00
4
2.1 Drawing tools
• Drawing instruments• Include instruments to draw circles• Compasses : friction-joint & spring
bow• Many sizes e.g.
– To draw small circles - up to 20mm radius
– To draw circles 5mm to 150mm radius
MEMB113 | MANUAL DRAWING | CHAPTER 2
7
ad
zly a
nuar
© 2
00
1-2
00
4
2.1 Drawing tools
• Measuring instruments– E.g scale rule
• Set squares– Several types
• 60o,30o set square• 45o set square• adjustable set square
MEMB113 | MANUAL DRAWING | CHAPTER 2
8
ad
zly a
nuar
© 2
00
1-2
00
4
2.1 Drawing tools
• Pencil and erasers– 18 degrees of hardness:
• from 9H – very hard• to 7B – very soft• normally it is recommended:
– 2H or H for construction, dimension, extension, leader, center lines
– HB or B for lettering, visible lines
• Instruments to aid drawing curves– French curves– Flexible curve
MEMB113 | MANUAL DRAWING | CHAPTER 2
9
ad
zly a
nuar
© 2
00
1-2
00
4
2.2 Drawing layout
• Drawing sheets– Usually based on 'A' series
• Drawing sheets material - paper, linen, plastic film
• Drawing sheet layout– Sheet frames or border– Usually 20mm for A0 & A1,
10mm for others
• Title block or title frame– Represents general information
source for a drawing– Usually at bottom right-hand
corner
A1
A2
A3
A4
A4
A0 : 1189x841
A1 : 841 x 594
A2 : 594 x 420
A3 : 420 X 297
A4 : 297 X 210
All in mm
MEMB113 | MANUAL DRAWING | CHAPTER 2
10
ad
zly a
nuar
© 2
00
1-2
00
4
2.2 Drawing layout
10m
m
10mm 10mm
Paper Size : A2 (594mm x 420mm)
regular paper size
drawing frame
UNIVERSTI TENAGA NASIONAL
TITLEALL DIMENSIONS IN mm
Border width : 10mm all round
NAME
150 150
30 45
10
Lettering height : 7mm
30
COURSE NO.
SID SECTION
SCALEDATE
MEMB113 | MANUAL DRAWING | CHAPTER 2
11
ad
zly a
nuar
© 2
00
1-2
00
4
2.3 Lettering
• Text is an important part of a technical drawing. Not all info required on technical dwg can be communicate graphically such as dimensions.
• One method of creating text is by freehand lettering. The standard style for freehand lettering is single-stroke Gothic lettering.
MEMB113 | MANUAL DRAWING | CHAPTER 2
12
ad
zly a
nuar
© 2
00
1-2
00
4
2.3 Lettering
• Characteristic of good lettering– Should be neat, not
sloppy– Should be uniform and
consistent i.e. same height, proportion & inclination – use guidelines
– Should have proper spacing of letters and words
– Should not contain unnecessary frills
MEMB113 | MANUAL DRAWING | CHAPTER 2
13
ad
zly a
nuar
© 2
00
1-2
00
4
2.3 Lettering
• Characteristic of good lettering– Should use capital letters except for
standard abbreviation e.g. mm, kg– Recommended minimum height 2.5mm– Recommended height 5mm to 7mm– Underlining of lettering should be
avoided
MEMB113 | MANUAL DRAWING | CHAPTER 2
14
ad
zly a
nuar
© 2
00
1-2
00
4
2.4 Lines
• Different line types for different purposes - to ensure drawing to be read quickly & accurately
• Types of lines and thickness of line• Commonly used line types & thickness:
Pencil
Description Usage Example
B/2B/0.5mm
Continuous thick
Drawing outlines & visible edges
Continuous thin
Hatching, dimension & projection lines
Continuous wavy thick
Limit of partial view
Dashed thin Hidden detail
Long & short dash thin
Center lines
2H/H/0.3mm
2H/H/0.3mm
2H/H/0.3mm
B/2B/0.5mm
MEMB113 | MANUAL DRAWING | CHAPTER 2
15
ad
zly a
nuar
© 2
00
1-2
00
4
2.4 Lines
Standard line types used in technical drawing
MEMB113 | MANUAL DRAWING | CHAPTER 2
16
ad
zly a
nuar
© 2
00
1-2
00
4
2.5 Scale
• What does it mean?• Scale used should always be stated on drawing –
important info that is usually written in the title block.• 'do not scale' / 'not to scale‘ / NTS – the drawing is
not drawn to a certain scale• Recommended scale
– 1:1 for full size– for greater than full size
• 2:1 for twice full size• 10:1 for ten times full size
– for reduced size• 1:2 for half full size• 1:10 for tenth full size
• other common scale - 1:5, 1:20, 1:50, 1:100, 1:500 etc.
MEMB113 | MANUAL DRAWING | CHAPTER 2
17
ad
zly a
nuar
© 2
00
1-2
00
4
2.6 Abbreviations
Word/ phrase AbbreviationsAssembly ASSYCentre line CL orChamfer CHAMCountersink CSINKCounterbore CBOREMaterial MATLMaximum MAXMinimum MINNumber NOPitch CircleDiameter PCDRadius RAD or RRequired REQD
Word/ phrase AbbreviationsCylinder CYLDiameter DIA orExternal EXTFigure FIGHexagon HEXInternal INTSpecification SPECSquare SQStandard STDMAX MATLcondition MMCVolume VOLWeight WT
MEMB113 | MANUAL DRAWING | CHAPTER 2
End of Chapter 2End of Chapter 2
Thank YouThank You