drawing lecture 2

CHAPTER 1 PART 2

INTRODUCTION TO

TECHNICAL DRAWING

Technical Drawing (EMP1102)

Part 2- Introduction to Engineering Drawing.

� Sheet Formats

� Line Types

� Dimensioning Rules and Schemes

Technical Drawing I (EMP1102)

Drawing Standards –Sheet Format

Example C-Size

Revision Block

Border

Zone Identifiers

This is zone C4

Notes

Title Block

Technical Drawing I (EMP1102)

Title block – information.

Technical Drawing I (EMP1102)

Rajah memberikan spesifikasi yang lengkap berhubung dengan jenis bahan, jenis

kekemasan permukaan, rawatan haba, dimensi dan hubungan geometri – sepusat.

limit

Material spec

Surface finishing

1st Angle Projection Heat Treatment

Tolerance

Technical Drawing I (EMP1102)

Drawing layout

Technical Drawing I (EMP1102)

For complete layout please refer Giesecke, Mitchell, Spencer, Hill,

Dygdon & Novsk. 2003. Technical Drawing. 12th Edition. New

Jersey : Prentice Hall, Figure 3.43 Page 59.

Drawing Paper Boarder Line and Title

Technical Drawing I (EMP1102)

Letters and Numbers � Freehand writing and write in single stroke technique.

� Lettering should all be in capitals and underlining should be avoided.

� Size should be at least 3mm on the finished drawing/ plot.

� With the normal paper in landscape orientation and the title block on the bottom right and side, notes to be parallel with the bottom edge.

� General notes shall be normally grouped together. Notes related to specific views may be located adjacent to the view.

� Spacing between words should be not less than 0.2h and not more than 0.6h.

� The height (h) in mm of characters for various drawing sheet sizes (A3,A2,A1) should be as follows:� Titles and drawing numbers: 5mm � Subtitles, headings, views and section : 3.5mm � General notes, materials lists and dimension : 2.5mm

Technical Drawing I (EMP1102)

LETTERING

Technical Drawing I (EMP1102)

Vertical Capital letters with single stroke technique lettering.

LETTERING

Technical Drawing I (EMP1102)

Inclined letters with single stroke technique lettering.

Technical Drawing I (EMP1102)

Use 3H pencil grade to draw the guide line

Use H or F pencil grade with 0.5 size to write the lettering or numbering.

Spacing between letters & numbers is 0.2h

Template to create quick guidelines for lettering.

Technical Drawing I (EMP1102)

LETTERING

Technical Drawing I (EMP1102)

Use 3H pencil grade to draw the guide line

Use H or F pencil grade with 0.5 size to write the lettering or numbering.

Spacing between letters & numbers is 0.2h

LINES – General information

Technical Drawing I (EMP1102)

•Generally, technical drawing is the expression of bodies (or matters) by lines.

•Pieces are composed of variable geometric component. Sides and surfaces of these components are visible but some of them can not be seen because they are behind the back sides.

•To obtain full and precise info about the piece, drawing should be done by using variable lines (instead of using same lines). Moreover, these lines should be drawn at same thickness and shape by everyone. The shapes and thicknesses of lines are given in TS88.

TYPES OF LINE

Type A

Type B

Type G

Type B

Type H

Type H

Type E

Technical Drawing I (EMP1102)

TYPES OF LINE

Type C

Type D

Type G

Type G

Type H

Technical Drawing I (EMP1102)

Break Lines

Dimension

Technical Drawing I (EMP1102)

Technical Drawing I (EMP1102)

Line thicknesses for various sheet sizes

Sheet

Size

LINE TYPE AND THICKNESS (mm)

A B C D E F G H J K

AO,B1 0.7 0.35 0.35 0.35 0.35 0.5 0.35 0.35/

0.7

0.7 0.35

A1,A2,

A3,A4,

0.5 0.25 0.25 0.25 0.25 0.35 0.25 0.25/

0.5

0.5 0.25

Type A – Visible out line

Type B – dimension, projection, hatching and leader line

Type C – short break line

Type D – ruled zigzag line

Type E – hidden outline line

Type D – centre line

Type H – cutting plane of the section

Type J – surface required special treatment

Type K – when drawing a component where it is necessary to show its

relationship to an adjacent part.

Technical Drawing I (EMP1102)