Drafting

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Drafting Product Design Architecture

• Basic Drafting Skills Alphabet of Lines

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Alphabet of Lines
The different lines and line symbols used on
drawings form a kind of graphic alphabet commonly
known as the alphabet of lines. Two line
widths-thick and thin-are generally used.
Drawings are easier to read when there is good
contrast among different kinds of lines. All
lines must be uniformly sharp and black.
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Visible Object Lines
Visible Object Lines are thick dark solid
(unbroken) lines that are used on drawings to
indicate the edges and details of an object.
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Visible Object Lines
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
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Hidden Lines
Hidden Lines are thin dashed lines used to
indicate a surface, edge, or contour of an object
that cannot be seen, or is hidden from view.
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Hidden Lines
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
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Center Lines
Center lines are thin lines made up of
alternating long and short dashes. They are used
to indicate the center of symmetrical features,
such as circles or arcs. They are used as an aid
in dimensioning.
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Center Lines
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
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Section Lines
Section Lines are thin cross hatching lines
used in sectional views to symbolize different
parts of an object or different materials from
which an object is manufactured.
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Section Lines
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
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Dimension, Extension Leader Lines
Dimension, Extension and Leader Lines are thin
lines used for dimensioning purposes. Dimension
and leader lines generally end with arrow heads
and are accompanied by a number indicating a size
or location dimension.
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Dimension, Extension Leader Lines
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
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Cutting Plane Lines
Cutting Plane or Viewing Plane Lines are very
thick lines that indicate where an imaginary
cutting plane passes through an object, for
viewing or sectioning purposes. Arrowheads on
both ends of the line point toward the surface to
be viewed.
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Cutting Plane Lines
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
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Break Lines
Break Lines are used to shorten a view, or to
eliminate repetitive details when an entire view
is not necessary. Short break lines are thick
wavy freehand lines. Long break lines are thin
straight zig-zags.
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Break Lines
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
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Phantom Lines
Phantom Lines are thin lines used to indicate
alternate positions of moving parts, lines of
motion, adjacent parts and repetitive details.
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Phantom Lines
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
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Drafting Product Design Architecture