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ENGINEERING

DRAWINGLECTURE 2

Introduction

• Engineering drawings are prepared on standard size

drawing sheets.

• For uniformity, the drawings must be drawn as per

standard practice.

Drawing Standards

Drawing Sheet Layout

• A drawing sheet has a standard form of arrangement

• A drawing space

• Title block

• All the important particulars are included.

• Grids along horizontal edges- Numerals

• Grids along vertical edges- Capital edges

Borders

• A space is left all around in between the trimmed

edges of the sheet

10 mm

25 mm

Title Block

• Title block lies within the drawing space at the bottom right hand corner of the sheet.

• Title block contains the following information:

• Title of drawing

• Drawing number

• Scale

• Symbol denoting the method of projection

• Name of firm

• Initials of staff who have designed, checked and approved.

Title block used in Engineering Firms

Title block for Students

LETTERING

Lettering

• Lettering is defined as writing of

• Titles

• Sub-Titles

• Dimensions

• ISO 3098-1:2015 specifies the general requirements for lettering, in accordance with the other parts of ISO 3098, to be used in technical product documentation (in particular on technical drawings).

• Lettering should be done freehand.

Main Features of Lettering

• Legibility

o The quality of being clear enough to read.

• Uniformity

o The quality or state of being uniform.

• Rapidity of execution

Single Stroke Letters

• Single stroke lettering means that the thickness of

letter should be uniform as obtained by one stroke of

the pencil.

• There are two types of single stroke letters;

• Type A : height of letter is divided to 14 equal parts

• Type B; height of letter is divided into 10 parts

Lettering

• These both types are further classified to two types:

• Vertical

• Inclined at 75⁰ with horizontal

• Vertical letters are preferred for fast and easy execution.

• Lettering should be done in CAPITALS

• Lower case alphabets are only used for abbreviations i.e. mm, cm etc.

Procedure

• Thin horizontal lines are drawn first at a distance h

apart.

• Horizontal lines are drawn from left to right.

• Vertical, inclined and curved lines are drawn from top

to bottom.

• After lettering has been completed , the guidelines are

not erased.

Guidelines for Lettering

• Drawing numbers, Drawing title and letters denoting cutting planes are written in 10 mm size.

• Name, Roll no. and Class are written in 7 mm size.

• Hatching, sub-titles, materials, dimensions are written in 3.5 mm size.

• Space between lines is 3

4of height.

• Space between words may be equal to the width of alphabet M.

• There should be a good visual spacing amongst letters.

Practice Problem

• Task 1:

Draw horizontal , vertical and inclined lines using

freehand

• Task 2:

Draw curves C and inverted C

• Task 3:

Write capital letters

Practice Problem

• Task 4:

Write small letters

• Task 5:

Write numerals in single stroke