TOPIC 1 - ENGINEERING GRAPHICS Flashcards
deals with the preparation of technical drawings for Engineering components like machine and buildings.
Engineering Drawing and Graphics
All engineering drawing are prepared in
Manual Drafting or Computer Aided Drafting
The set of conventional symbols covering all the lines needed for different purposes is called
The Alphabet of Lines
The Thick lines drawn using
H or F for pencil and 0.5 mm for inking
Thin lines are drawn using
6H or 5H for pencil, and 0.2mm for inking.
Alphabet of Lines Enumerate
Visible Outline
Invisible Outline
Center line
Center line, in pencil
Dimension LIne
Extension Line
Alternate Position
Line of Motion
Cutting plane
Repeat line
Broken Material
Limiting Break
Cross-hatching Line
used for laying out a drawing
Construction Lines
used to keep lines of lettering in perfect alignment
Guideline
describe the visible surface of edge of the object
Object lines
represents an invisible edge on an object
Hidden lines
used to show and locate the centers of circles
Centerlines
used to represents the center axis of a circular or symmetrical form
Centerlines
used to establish the extent of a dimension
Extension lines
begins with a short space from the object and extend to about 2mm beyond the last dimension
Extension lines
may cross object lines, centerline, hidden lines and other extension lines.
Extension lines
are thin lines capped on the ends with arrowhead and broken along their length to provide a space for the dimension numeral.
Dimension Lines
used to connect a specific note to a feature
- common angles 30, 45, 60
- avoid 75, greater than 15
Leader lines
are used to terminate dimension lines an leader lines
Arrowheads
used to identify where a sectional view is taken
Cutting - plane lines
used to identify where a view is taken for view enlargement or for partial views
Viewing -plane lines
used in the view of a section to show where the cutting plane line has cut through the materials
Section lines
short break and long break
Break lines
are thick af alternately spaced and long dashes used to indicate that the portion of the surface next to the chain line receives some special treatment
Chain lines
thin short dashes or 0.5 mm diameter dots spaced 0.12 in apart
Stitch lines
are used to indicate a sewing or stitching process
Stitch lines
can be combined to form
any 15 angle increment.
The 45 and 30-60 triangles
Triangle Wheel
