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CHAPTER 2. Introduction to Manual Drawing. MEMB113 | MANUAL DRAWING | CHAPTER 2. Contents. Drawing tools Drawing sheets and layout Lettering Lines Scale Abbreviations. MEMB113 | MANUAL DRAWING | CHAPTER 2. 2.1 Drawing tools.
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CHAPTER 2 Introduction to Manual Drawing
MEMB113 | MANUAL DRAWING | CHAPTER 2 Contents • Drawing tools • Drawing sheets and layout • Lettering • Lines • Scale • Abbreviations
MEMB113 | MANUAL DRAWING | CHAPTER 2 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 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 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 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 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 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 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 2.2 Drawing layout
MEMB113 | MANUAL DRAWING | CHAPTER 2 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 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 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
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 MEMB113 | MANUAL DRAWING | CHAPTER 2 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: 2H/H/ 0.3mm B/2B/ 0.5mm 2H/H/ 0.3mm 2H/H/ 0.3mm
MEMB113 | MANUAL DRAWING | CHAPTER 2 2.4 Lines Standard line types used in technical drawing
MEMB113 | MANUAL DRAWING | CHAPTER 2 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 2.6 Abbreviations
End of Chapter 2 Thank You