Drafting Theory
Take Notes: You can use your hand written notes during the tests
Purpose, Standards and Drawing Materials
What is Drafting?
· It is a graphic (pictures) language.
· Artistic Drawing - expresses a feeling.
· Technical Drawing (drafting) - expresses an idea.
· It is a graphic (pictures) language.
· Artistic Drawing - expresses a feeling.
· Technical Drawing (drafting) - expresses an idea.
The Purposes and Advantages of Drafting?
· Used to communicate and develop ideas.
· It is universal:
· Drawings can be understood worldwide.
· Standards are needed otherwise drawings could not be used in another place easily.
· In Canada, standards are decided by the Canadian Standards Association (CSA).
· Used to communicate and develop ideas.
· It is universal:
· Drawings can be understood worldwide.
· Standards are needed otherwise drawings could not be used in another place easily.
· In Canada, standards are decided by the Canadian Standards Association (CSA).
Pencils
· Darkness is determined by the width of the line and the amount of graphite in the pencil.
· Pencil lead is made up of graphite, clay and resin (usually).
Harder / Lighter ---------------------------------------------------------- Softer / Darker 9H---7H---6H---5H---4H---3H---2H---H---F---B---2B---3B---4B---5B---6B---7B
· 4H (very light line weight) is used for construction lines, and guidelines (used in lettering).
· 4H or 2H (medium line weight) is used for hidden lines, centerlines and section lines.
· HB (dark line weight) for visible or bodylines and lettering.
Pens
· Inking - darkness is determined by the width of line only.
Drawing Materials
· Some Types of Print Media:
· Regular Bond Paper - does not erase well.
· Plotting Bond Paper
· Tracing Paper
· Vellum - erases well but is expensive.
· Mylar - plastic very strong and expensive.
Media Sheet Sizes
· Sheet sizes are multiples of the standard 8-1/2" x 11” sheet of paper.
· This allows for the sheets to be folded down to fit a 9” x 12” envelope.
· Metric sizes are similar to imperial sizes.
· Darkness is determined by the width of the line and the amount of graphite in the pencil.
· Pencil lead is made up of graphite, clay and resin (usually).
Harder / Lighter ---------------------------------------------------------- Softer / Darker 9H---7H---6H---5H---4H---3H---2H---H---F---B---2B---3B---4B---5B---6B---7B
· 4H (very light line weight) is used for construction lines, and guidelines (used in lettering).
· 4H or 2H (medium line weight) is used for hidden lines, centerlines and section lines.
· HB (dark line weight) for visible or bodylines and lettering.
Pens
· Inking - darkness is determined by the width of line only.
Drawing Materials
· Some Types of Print Media:
· Regular Bond Paper - does not erase well.
· Plotting Bond Paper
· Tracing Paper
· Vellum - erases well but is expensive.
· Mylar - plastic very strong and expensive.
Media Sheet Sizes
· Sheet sizes are multiples of the standard 8-1/2" x 11” sheet of paper.
· This allows for the sheets to be folded down to fit a 9” x 12” envelope.
· Metric sizes are similar to imperial sizes.