ALPHABET OF LINES -TECHNICAL DRAWING
Summary
TLDRIn this educational video, Sarah Ravi introduces grade seven students to the alphabet of lines in technical drawing. She explains various types of lines such as borderline, visible line, hidden line, center line, extension line, and dimension line, each with its specific use and appearance. She also covers cutting plane, long break, short break, and leader lines. A review test follows, encouraging students to identify these lines in a drawing, aiming to solidify their understanding of technical drawing fundamentals.
Takeaways
- 📏 **Borderline**: The heaviest and darkest line in a drawing, typically used to outline the main boundaries.
- 👀 **Visible Line**: Also known as object line, it represents the visible edges of an object.
- 🙈 **Hidden Line**: Represented by a medium weight dash, used to indicate the hidden or invisible edges.
- ➡️ **Extension Line**: Indicates the limit of a dimension line, often extending beyond the object.
- 📐 **Dimension Line**: Shows measurements and is usually accompanied by numerical values and arrowheads.
- 🔪 **Cutting Plane Line**: Thick lines used to show where a section has been taken in a drawing.
- 🚧 **Long Break Line**: Used to limit the presentation of a longer or larger object in a drawing.
- 🎯 **Center Line**: Shows the center in holes or circular objects, represented by alternating short and long dashes.
- 📝 **Reference Line**: An irregular fine curved line with an arrowhead at one end, used to point to a specific part.
- 🔢 **Review Test**: The script includes a review test to practice identifying different types of lines in technical drawings.
Q & A
What is the borderline in technical drawing?
-The borderline is the heaviest and darkest line in a drawing, which outlines the edges of the object.
What is another name for the visible line?
-The visible line is also known as the object line, representing the visible edges of an object.
How is a hidden line represented in technical drawing?
-A hidden line is represented by a medium weight dash, used to show the hidden or invisible edges of an object.
What does an extension line indicate in technical drawings?
-An extension line indicates the limit of a dimension line, usually extending beyond the object to show the measurement.
What is the purpose of a dimension line?
-A dimension line is used to show measurements, often with numerical values and arrowheads indicating the dimension.
What is the cutting plane line used for?
-The cutting plane line is used to show where a section has been taken, typically represented by thick lines.
How is a center line depicted in technical drawings?
-A center line is depicted with a short dash and another long dash, used to show the center in holes of circular objects or shapes.
What is the function of a reference line in technical drawings?
-A reference line is an irregular fine curved line with an arrowhead at one end, used to point to a particular part on a drawing.
What is the difference between a long break line and a short break line?
-A long break line is used to limit the presentation of a longer or bigger object, while a short break line is used for smaller or shorter objects.
What is the significance of a section line in technical drawings?
-A section line is usually at a 45-degree angle and is used to indicate where a section of the object has been cut open for viewing.
How can one improve their understanding of the alphabet of lines in technical drawing?
-One can improve their understanding by reviewing the video, practicing identifying different types of lines in drawings, and taking a review test.
Outlines
📐 Introduction to Technical Drawing Lines
In the first paragraph, Sarah Ravi introduces the technical drawing class for grade seven students. The lesson focuses on the alphabet of lines, starting with the borderline, which is the heaviest and darkest line in a drawing. The visible line, also known as the object line, represents visible edges. The hidden line, indicated by a medium weight dash, shows the hidden or invisible edges of an object. Extension lines show the limit of a dimension line, and dimension lines carry numerical values and arrowheads to represent measurements. The cutting plane line uses thick lines to indicate where a section has been taken. Long break lines limit the presentation of larger objects, while center lines, represented by short and long dashes, show the center of holes or circular objects. Reference lines are irregular fine curved lines with arrowheads to point out specific parts on a drawing.
📝 Review Test on Alphabet of Lines
The second paragraph presents a review test on the alphabet of lines. It lists various types of lines such as borderline, visible line, hidden line, center line, extension and dimension lines, and cutting plane line. The paragraph then provides a drawing for students to analyze and identify different types of lines by numbering them. The test includes identifying dimension lines by their numerical values and arrowheads, extension lines by their role in limiting dimension lines, center lines by their association with circular holes, hidden lines by their representation of short dashes for invisible edges, and section lines. The paragraph concludes with visible lines and leader lines, and a cutting plane line. Students are encouraged to review the video if they do not achieve a perfect score.
Mindmap
Keywords
💡Borderline
💡Visible Line
💡Hidden Line
💡Extension Line
💡Dimension Line
💡Cutting Plane Line
💡Long Break Line
💡Short Break Line
💡Center Line
💡Reference Line
💡Leader Line
Highlights
Introduction to the technical drawing class for grade seven students.
Topic for the day: Alphabet of lines.
Definition of borderline: the heaviest and darkest line in a drawing.
Visible line, also known as object line, represents visible edges.
Hidden line represented by a medium weight dash for invisible edges.
Extension line indicates the limit of a dimension line.
Dimension line is used to show numerical values and has arrowheads.
Cutting plane line is used to show where a section has been taken.
Long break line is used to limit the presentation of longer or bigger objects.
Center line is used to show the center in holes of circular objects.
Reference line is an irregular fine curved line with an arrowhead used to point a particular part.
Review test about the alphabet of lines with a drawing to analyze.
Test question on identifying borderline in a drawing.
Test question on identifying visible line in a drawing.
Test question on identifying hidden line in a drawing.
Test question on identifying center line in a drawing.
Test question on identifying extension line in a drawing.
Test question on identifying section line in a drawing.
Test question on identifying visible edges in a drawing.
Test question on identifying leader lines in a drawing.
Test question on identifying cutting plane line in a drawing.
Encouragement to review the video for a perfect score.
Transcripts
[Music]
foreign
[Music]
[Applause]
grade seven students and to my fellow
technical drawing teachers my name is
Sarah Ravi and welcome to my technical
drawing class for grade seven
so our topic for today is about alphabet
of lines
start with the borderline
borderline this is generally the
heaviest and darkest line in a drawing
usually it is
again this is the heaviest and the
darkest line in a drawing which is the
borderline
the next one is the visible line this
line is also known as object line into
usually
visible edges
unlike the borderline
again visible line this line is also
known as object line
next hidden line is represented by a
medium weight Dash used to show the
hidden or invisible edges of an object
hidden line
okay again it is used to show the hidden
or the invisible edges line
[Music]
extension line extension line indicates
the limit of a dimension line
Dimension line and dimension line at the
shot
usually partnership
at my numerical value
Dimension line Anonymous
[Music]
color red
line
next line is cutting plane line it is
used to show where a section has been
taken
thick lines again it is used to show
where a section has been taken and that
is cutting plane line
next long brake line it is used to limit
the presentation of a longer or bigger
object
line
is
limit the presentation of a longer or
bigger object
[Music]
next is Center Line Center Line it is
used to show the center in holes of
circular object or shape
[Music]
Center Line manifest s
my short Dash and another long Dash
and that is Center Line
next reference line it is an irregular
fine curved line with an arrow head at
one end used to point a particular part
on a drawing hello
my irregular fine curved line
next
okay
alphabet of lines the first one is the
borderline
visible line hidden line
center line
extension and dimension line against
partner Lage see Dimension line you my
arrowheads at my numerical value so
extension line demand I not the limit
Chi Dimension line
okay neither line attention because
irregular find curved line we have also
section 9 online are usually have a 45
degrees then
and cutting plane line
long brake line and short break line
[Music]
okay
let's have a review test about alphabet
of lines
okay so try to analyze this object or
this drawing
designate numbers drawing
foreign number one
alphabet of line again
so number two
alphabet of line again
number one
number three
Nino
circular objects
number four
short dashes
number five
number six
[Music]
number seven
alphabeto
number eight
foreign
all right
let's try to answer for number one
the answer is
Dimension line Market Dimension line
because my numerical value my
measurement and then my arrowheads
number two
limit okay Dimension line the answer is
extension line
number three
circular holes
the answer is Center Line
about number four
short dashes
invisible or hidden edges the answer is
hidden line how about number five
do you think is the answer the answer is
short break line number six
okay the answer is
section line how about number seven
visible edges
there is
visible line how about number eight
answer is
leader lines
the last number
answer is
cutting plane line how's your score is
it perfect score if not you can re-watch
and review this video
Perfect answer
and that's it for today
grade seven and good luck
[Music]
Weitere ähnliche Videos ansehen
5.0 / 5 (0 votes)