Introduction
Technical Drawing
Tools & Lettering
Books
Boo
Basics of Engineering Drawing
Reference Books
by Zahid Ahmed Siddiqi
Geometric and Engineering Drawing by K. Morling
Blueprint Reading: Construction Drawings for the Building Trades
by Sam A. A. Kubba, Ph.D.
GRAPHICS LANGUAGE
Effectiveness of Graphics Language
-
Try to write a description of this object.
-
Test your written description by having someone attempt to make a sketch from your description.
The word languages are inadequate for describing the size, shape and features completely as well as concisely.
You can easily understand that …
lines to represent the surfaces, edges and contours
of objects.
use
Graphic language in “engineering application”
Composition of Graphic Language
“drawing“
The language is known as or “drafting” .
A drawing can be done using freehand, instrumentsor computer methods.
Freehand drawing
The lines are sketched without using instruments other than pencils and erasers.
Example
Instrument drawing
Instruments are used to draw straight lines, circles, and curves concisely and accurately. Thus, the drawings are usually made to scale.
Example
Computer drawing
The drawings are usually made by commercial software such as AutoCAD, BIM etc.
Example
Engineering Drawing
Engineering drawing are made up of graphics language
and word language.
Describe a shape
(mainly).
Describe size, location and
specification of the object.
Word language
Graphics language
Elements of Engineering Drawing
Traditional Drawing Tools
T-Square 2. Triangles
2H or HB for thick line 4H for thin line
- Adhesive Tape 4. Pencils
5. Sandpaper 6. Compass
7. Pencil Eraser 8. Erasing Shield
9. Circle Template 10. Tissue paper
11. Sharpener 12. Clean paper
Lettering
Text on Drawings
Text on engineering drawing is used :
To communicate nongraphic information.
As a substitute for graphic information, in those instance where text can communicate the needed information more clearly and quickly.
Example Placement of the text on drawing
Dimension & Notes
Notes Title Block
Lettering Standard
ANSI Standard This course
Use a Gothic text style,
either inclined or vertical.
Use all capital letters.
Use 3 mm for most text height.
Space between lines of text is at least 1/3 of text height.
Use only a vertical Gothic text style.
Use both capital and lower-case letters.
Same. For letters in title block it is recommend to use 5~8 mm text height
N/A.
Follows ANSI rule.
Curved
Horizontal
Slanted
Straight
Basic Strokes
Examples : Application of basic stroke
“I” letter 1
“A” letter 1 2
3
4 5
“B” letter 1
3 6
2
Upper-case letters & Numerals
Straight line letters
Curved line letters
Curved line letters & Numerals
The text’ s body height is about 2/3 the height of a capital letter.
Example : Good and Poor Lettering
GOOD
Not uniform in style. Not uniform in height.
Not uniformly vertical or inclined.
Not uniform in thickness of stroke.
Area between letters not uniform. Area between words not uniform.
Leave the space between words equal to the space requires for writing a letter “O”.
Sentence Composition
Example
ALL
O DIMENSIONS
O ARE
O IN
MILLIMETERS
OTHERWISE
O UNLESS
O SPECIFIED.
*98/te
