Transcript CHAPTER 3
CHAPTER 3:
Drafting Equipment
Mrs. Kampf
Engineering Graphics I
Drafting Board
Drawing sheet attached to it.
9X12, 16X21 or 18X24
Wood with vinyl cover
Stay flat and straight
T-Square
A head that lines up with a true edge of
the drafting board
Straightedge provides a true edge
Metal, wood with plastic
Triangles
Used with t-square
45° has a 90° angle and two 45°
30° -60° triangle has a 30° a 60° and a 90°
Protractor
Used to measure or lay out angles
right, acute, obtuse
Irregular Curves
French curves
Used to draw noncircular curves like
spirals and ellipses.
Templates
Save time in drawing shapes of details.
Vellum
Tracing paper that has been treated to
make it more transparent.
ANSI
American National Standards Institute
ISO
International Standards Organization
Paper
Size A - Letterhead 8.5” X 11”
Size B - Tabloid 11” X 17”
Size C - 17” x 22”
Size D - 22” X 34”
Size E - 34” X 44”
Case instruments
Drawing instruments that come in a set.
Dividers
Lines can be divided and distances can be
transferred with this
Bow and Friction-joint
Compass
True circles or arcs can be drawn with
this
Bow and Friction-joint
Bow instruments
Can be adjusted with either a center
wheel or a side wheel
Easy to use and accurate.
Graphite pencils
17 degrees of hardness or grades
Grade you use depends on paper type,
line weight and darkness of lines made
6B to 9H, #2/HB is middle
Hardness, Blackness, Fine Point
Eraser
Vinyl erasers for film, kneaded, pink pearl,
gum, Magic rub
Erasing shield
Use to avoid erasing nearby lines
accidentally
Plastic or metal and have different size
and shape openings
Scales
Instruments used to lay off distances and
make measurements
Full size or some proportion
Scaled.
Architect’s scale
Inch Scale
Divided into proportional feet’ and inches”
Used for drawing buildings
Mechanical Engineer’s scale
Inches and fractions of an inch divided to
represent inches
Use for drawing machine parts
Civil Engineer’s scale
Inches divided into decimals
Units could be inch, feet, miles etc
Used for maps and drawings of roads