WEBVTT

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>> So in this lecture,
we're going to talk

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about sectional views
or sectioning in terms

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of the need for visualization.

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This chapter can
be typically one

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of the most difficult
for a student.

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So be a little patient
especially in the beginning

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if you're having
problems visualizing.

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Sectional views are nothing but
additional orthographic views,

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okay, that we create in order
to expose internal features

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of the objects especially
features

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that will normally appear in a
standard front upright views.

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Here's an illustration.

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Here's a 3D object.

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And it's very easy to visualize
if you have the isometric.

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Here's the top view and
here's the front view.

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And what we notice in this
normal multiview drawing is

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that the front has a
lot of hidden lines.

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We know from experience that the
more hidden lines an object has

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in the view the more difficult
it is to visualize that object.

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So the hidden lines here
in the front view indicate

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that some parts are empty
and some parts are solid.

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And we need to help our
audience determine which parts

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of the drawing are solid,
which parts are empty.

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And the way we do that is by
creating a sectional view.

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And we do that by
imagining a cutting plane.

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Here's the cutting plane
here and in this case,

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we make that cutting plane
slice right through the middle

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of the object like this and then
we remove the part of the object

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that is in front of
that cutting plane.

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So we remove the front part
and then we look at the object

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in the same direction
as the front.

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The arrows here indicate the
direction of the line of sight.

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In the normal standard views,

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we indicate the cutting
plane's position right here.

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This is the actual the cutting
plane as show in the top view

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and here's the directional
of line of sight.

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And the view below the top
view is now the front view

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after taking the cutting section
and removing the front part.

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Now we realize that all this
section areas here are the solid

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parts of the original
object that were sliced

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through by the cutting plane.

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So the hidden lines here

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in the original front
view now become solid.

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These are now visible
because we've sliced

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and removed the front
part and as you can see,

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we indicate this part
here with section lines

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that evenly spaced the 45
degree lines on this area

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and this area indicating that
those two L-shaped areas,

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this L-shape area and inverted
L-shape here are solid parts

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of the object that
were directly sliced

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through by the cutting plane.

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Other hidden lines like this
two circles here becomes solid

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because now you can
see those two circles

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after removing the front
half of the object.

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So as we noticed,
sectional views have the

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following elements.

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Cutting planes, okay.

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That's the plane you use to
slice the object into two parts

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and it's shown in one of the
standard views as an edge view.

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We have this 3D solid
object that has --

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looks like a shell and there
are some other features inside

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that we don't know and we're
trying to clarify that.

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As seen in the front view here,
you have a lot of hidden lines.

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So what we do is we
take a cutting plane,

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we also include a
cutting plane arrow.

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In this case, these 2 arrows
here indicate the direction

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of the line of sight.

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After you slice the object,

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we also have section
lines right here.

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An element of the
actual full section.

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These are the front view here

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and this arrow view's
here has been replaced

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by a full section view.

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And the section lines or
hashing indicate areas

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where solid material
has been cut

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through by the cutting plane.

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Okay? Here's another
illustration.

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Here is the 3D object.

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Before we cut it, we
indicate the position

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or it's in isometric.

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So we indicate the position
of the cutting plane

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and the direction of
the line of sight.

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We remove in this case 
right part.

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There is a couple of different
ways of indicating the position

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of the cutting plane
and it's edge view.

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Okay? The most common one is
using this long short short long

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series of lines.

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Okay? Or this could
also be dash.

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I do not like this dash here

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because sometimes
student confuse it

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with regular hidden line.

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I prefer this line type.

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With respect to the section
lines or the hashing,

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they should be evenly spaced
between one sixteenth of an inch

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to one eighth of an inch
in the final drawing.

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Generally they should be about
45 degrees but not parallel

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or perpendicular to the
outline of the object.

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I will show you an
example of this later

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and why you should avoid that.

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There are symbols
that correspond

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to a particular type
of material.

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And I will explain that later.

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So with respect to
the 45 degree, okay,

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so generally okay do you the
section lines along 45 degrees

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unless the 45 degree direction
end up being either parallel,

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in this case here,
to major object lines

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or perpendicular to
the object lines.

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And the reason why we
avoid cases a and b is

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because your audience
might confuse

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between actual object
lines and the section lines

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that are either parallel
or perpendicular.

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So in cases like this, you
just go a long direction

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in that case, neither
parallel nor perpendicular

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to major object.

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The symbols for the section
lines also give you additional

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information about the model.

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The generic symbol is
this equally spaced line.

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So you use this is if
you do not know what type

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of material you have.

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It's also used for cast
iron or malleable iron.

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Generally used for all
types of materials.

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Here's for steel.

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Here's for bronze.

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So different materials
that are commonly used

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in engineering have
different hash symbols.

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The good thing is you do
not have to memorize this

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because AutoCAD has a
built-in library of materials.

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As a general rule
for sectional views,

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we do not show hidden lines.

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Here's the 3D object
shown in its isometric

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and here's the position
of the cutting plane

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and the direction of
the line of sight.

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Here's the original top view
and the original front view

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and we choose to position of
cutting plane right here passing

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through this hole in order to
expose these features here

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in the front view
that are mostly here.

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So here's the position
of the cutting plane.

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So we cut it here and here's
the resulting front view.

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And notice that this
solid line here came

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from this line here
that is not exposed.

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However that solid line is
this solid line in the middle.

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This hidden line in the middle.

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These 2 hidden lines here,
one to the left and one

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to the right correspond
to this back area here.

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This one line, one
edge going down here.

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Another edge going down
here which we did not expose

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because our cutting plane
did pass through those edges.

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But notice that those two hidden
lanes, the one on the left here

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and one on the right
here are not shown here.

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Why? Because generally even
those those lines still exist

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corresponding to the edge
here and this edge here,

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we don't show them because it
kind of defeats the purpose

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of the cutting -- or
the sectional view.

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The main purpose of taking
this sectional view right

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at this position is to
expose these features here

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and leaving the hidden lines
there would create confusion.

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Visualization of sectional
views can be challenging

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because now you're
not just trying

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to visualize how the object
looks from the outside,

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you're also imagining having
to slice through the middle

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of the object and then trying
to expose the internal features.

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And like we did for
multiviews and isometrics,

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it is often very
helpful to label planes

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as well as vertices.

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Some illustrations
of sectional views.

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Here's the regular top view
and the regular front view

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and regular right side view.

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And we're going to
try to attempt

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to expose the internal
features in the right side view

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as indicated by this hidden line

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by taking this cutting
plane here.

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So slicing it right through
here and removing this part

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and looking at it in this
direction, of course,

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that will result in
our right side view

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with its hidden lines
being converted

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into the sectional view.

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The way it's illustrated
here is you look at the parts

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of the object that were solid
right here that was sliced

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by your cutting plane.

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Don't forget to indicate
the section lines

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or the other solid
parts over here.

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And then do not forget that
although you need not slice

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through the cylindrical surface,

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the cylindrical surface here
curving this way was not

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directly sliced by the cutting
plane except for the quadrant

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up here and the quadrant
up there, down here.

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However, you still see this
line here corresponding the

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cylindrical surface here and
another line here corresponding

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to this cylindrical surface and
also the cylindrical surface

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of this smaller hole here.

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On the other hand,
there's no line here

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because this is not a
cylindrical surface.

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There is actually
an empty space.

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Different parts of
sectional views.

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The most common type
is a full section.

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It's called a full section

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because the cutting planes
cuts fully through the object

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and removing exactly
half of the object.

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So here's an example.

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The regular top view and
regular front view, okay,

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as you can see there's a lot of
hidden lines in the front view.

00:10:15.556 --> 00:10:17.466 A:middle
So what we do is
we're going to try

00:10:17.466 --> 00:10:19.366 A:middle
to clarify those
internal features

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by taking this cutting plane
and taking this line of sight,

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removing the front
half as indicated here

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and showing what's now visible.

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So this the cutting plane

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and here's the resulting
full section

00:10:36.226 --> 00:10:40.786 A:middle
with this hidden lines being
replaced by solid lines

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and then this line
is a curved line here

00:10:44.016 --> 00:10:45.896 A:middle
and this line correspond
to this.

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These two solid lines correspond
to these two lines here

00:10:49.106 --> 00:10:54.476 A:middle
and as you can see the left and
the right sides were solid parts

00:10:54.476 --> 00:10:57.126 A:middle
of the object that were
cut through or sliced

00:10:57.126 --> 00:10:59.016 A:middle
through by your cutting plane.

00:10:59.156 --> 00:11:03.036 A:middle
Notice how the hidden lines
become solid lines and now serve

00:11:03.036 --> 00:11:05.556 A:middle
as boundary of section
lines or hashed.

00:11:06.436 --> 00:11:10.016 A:middle
Half section is one
that does not cut

00:11:10.236 --> 00:11:12.196 A:middle
through fully through
the object.

00:11:12.366 --> 00:11:15.526 A:middle
Instead only passes
halfway through the object

00:11:15.526 --> 00:11:18.416 A:middle
and this is usually useful
for symmetric objects.

00:11:18.656 --> 00:11:20.986 A:middle
An object here is
the regular top view

00:11:21.526 --> 00:11:23.006 A:middle
and here's the regular
front view.

00:11:23.926 --> 00:11:26.656 A:middle
We take a cutting
plane over here.

00:11:27.226 --> 00:11:32.056 A:middle
Okay, but instead of the cutting
plane cutting fully like this.

00:11:32.306 --> 00:11:35.546 A:middle
It only goes through
half of the left half.

00:11:35.546 --> 00:11:38.166 A:middle
And take note that the
cutting plane goes this way

00:11:38.546 --> 00:11:39.486 A:middle
and then stops there.

00:11:40.256 --> 00:11:41.816 A:middle
And here's the direction
of the line of sight.

00:11:41.816 --> 00:11:47.816 A:middle
So basically we remove the left
half of the front of the object.

00:11:48.076 --> 00:11:52.386 A:middle
So as we expose here, this
hidden lines here become solid

00:11:52.386 --> 00:11:54.906 A:middle
and they become boundaries
for the section line.

00:11:55.306 --> 00:11:58.846 A:middle
Notice, however, that if
you compare the right part

00:11:58.846 --> 00:12:01.916 A:middle
of the regular front view and
the right part of the front view

00:12:02.146 --> 00:12:04.166 A:middle
of the sectional view notice

00:12:04.166 --> 00:12:07.606 A:middle
that we now have
removed the hidden lines.

00:12:08.176 --> 00:12:09.966 A:middle
That's generally, as we said

00:12:09.966 --> 00:12:14.316 A:middle
as a general rule we do
not show hidden lines.

00:12:14.316 --> 00:12:17.176 A:middle
Another side of section
is an offset section.

00:12:17.176 --> 00:12:19.066 A:middle
Here's an illustration
of an offset section.

00:12:19.646 --> 00:12:22.066 A:middle
Okay? So instead of
one whole plane cutting

00:12:22.066 --> 00:12:27.846 A:middle
through the object, the cutting
plane line is not straight

00:12:27.846 --> 00:12:29.966 A:middle
but it's offset in order to pass

00:12:29.966 --> 00:12:31.596 A:middle
through important
features of the object.

00:12:31.596 --> 00:12:34.946 A:middle
So this is what we do is
we just offset the position

00:12:35.526 --> 00:12:37.166 A:middle
and here's the directional
line of sight

00:12:37.246 --> 00:12:40.406 A:middle
and then we remove this
part that is in front

00:12:40.406 --> 00:12:42.486 A:middle
of the offset cutting plane.

00:12:42.486 --> 00:12:46.976 A:middle
Notice that we don't
show the cut form.

00:12:46.976 --> 00:12:51.116 A:middle
So right here where I actually
did the bent right here.

00:12:51.116 --> 00:12:52.616 A:middle
So it's going through here

00:12:52.616 --> 00:12:55.296 A:middle
and then bent backwards a
little bit, the actual position

00:12:55.296 --> 00:12:56.616 A:middle
of that is not important.

00:12:56.616 --> 00:12:59.156 A:middle
It could have been slightly
to the right or slightly

00:12:59.206 --> 00:13:02.396 A:middle
to the left and as a
result, we do not need

00:13:02.396 --> 00:13:06.196 A:middle
to show the cut formed by the
offset because in reality,

00:13:06.196 --> 00:13:08.516 A:middle
if my cutting plane
had to bend here,

00:13:08.516 --> 00:13:09.736 A:middle
there should be a
solid line here

00:13:09.736 --> 00:13:11.976 A:middle
and notice we don't
show that solid.

00:13:12.656 --> 00:13:15.136 A:middle
Okay? Because it's not important
in what we're trying to do.

00:13:15.136 --> 00:13:19.916 A:middle
What we're trying to do is
simply expose the features along

00:13:19.916 --> 00:13:21.986 A:middle
this position here
of the cutting plane.

00:13:22.616 --> 00:13:26.716 A:middle
Aligned section is one in
which it's cut at an angle

00:13:26.986 --> 00:13:29.186 A:middle
and it's usually used
for the circular shapes.

00:13:29.186 --> 00:13:30.266 A:middle
It's cut at an angle.

00:13:30.266 --> 00:13:33.476 A:middle
So here's the position of
the actual cutting plane.

00:13:34.216 --> 00:13:39.296 A:middle
So in this way and then
bent along here, an angle.

00:13:39.706 --> 00:13:46.076 A:middle
Now if we rely on this actual
direction of a cutting plane

00:13:46.076 --> 00:13:48.686 A:middle
and we look at it from
the right, you will see

00:13:48.686 --> 00:13:53.296 A:middle
that the holes here will
actually be foreshortened

00:13:53.456 --> 00:13:56.086 A:middle
because here the upper part
of the cut through the hole

00:13:56.086 --> 00:13:57.186 A:middle
and here's the lower part.

00:13:57.376 --> 00:14:00.296 A:middle
Okay? We look at it
directly from the right,

00:14:00.576 --> 00:14:02.806 A:middle
okay this arm here will
actually be shorter

00:14:02.806 --> 00:14:04.406 A:middle
than it's actual length

00:14:05.136 --> 00:14:09.066 A:middle
because we're not viewing
the length perpendicular

00:14:09.066 --> 00:14:10.086 A:middle
to the length itself.

00:14:10.086 --> 00:14:12.376 A:middle
So it kind of defeats
the purpose of trying

00:14:12.376 --> 00:14:16.896 A:middle
to clarify the object to the
sectional view so instead

00:14:16.896 --> 00:14:20.156 A:middle
of viewing it entirely from
the right, what we do is

00:14:20.156 --> 00:14:26.196 A:middle
for the angled cut, we imagine
that this arm is rotated

00:14:26.726 --> 00:14:28.296 A:middle
into this vertical position.

00:14:28.936 --> 00:14:32.086 A:middle
And that's why this
is lowest part, okay,

00:14:32.086 --> 00:14:33.286 A:middle
which should have corresponded

00:14:33.286 --> 00:14:37.016 A:middle
to this vertical position
is now all the way down here

00:14:37.016 --> 00:14:40.586 A:middle
because this whole arm
is imagined to be rotated

00:14:41.626 --> 00:14:48.516 A:middle
into vertical position and that
way we actually see the actual

00:14:48.516 --> 00:14:51.806 A:middle
size of this hole.

00:14:52.466 --> 00:14:55.546 A:middle
Another type of sectional
view is the phantom section.

00:14:56.046 --> 00:14:57.956 A:middle
This is the exception
to the rule

00:14:58.496 --> 00:15:01.936 A:middle
that there are no hidden
lines in a sectional view.

00:15:02.236 --> 00:15:06.826 A:middle
So in a phantom section, then
in a phantom section we --

00:15:06.826 --> 00:15:11.026 A:middle
although we still indicate the
position of the cutting plane

00:15:11.126 --> 00:15:14.366 A:middle
and the direction of the line
of sight, it's a phantom section

00:15:14.366 --> 00:15:16.666 A:middle
because we do not really
cut -- take the cut.

00:15:17.486 --> 00:15:19.806 A:middle
We don't cut through here
and remove the front part.

00:15:20.276 --> 00:15:25.706 A:middle
Instead we just imagine that we
have x-ray vision like Superman

00:15:26.216 --> 00:15:30.466 A:middle
that can penetrate the solid
objects to expose what's inside.

00:15:31.056 --> 00:15:34.196 A:middle
What you do is take
the regular front view,

00:15:34.296 --> 00:15:37.786 A:middle
here's the regular front
view okay and instead

00:15:37.846 --> 00:15:41.516 A:middle
of the regular section,
you cut this line here.

00:15:41.516 --> 00:15:43.566 A:middle
This cutting plane
here and then some

00:15:43.566 --> 00:15:45.816 A:middle
of this line will
become solid, okay,

00:15:46.136 --> 00:15:47.916 A:middle
and then you add the section.

00:15:47.916 --> 00:15:51.696 A:middle
In this case, none of the
hidden lines will be changed.

00:15:52.356 --> 00:15:56.836 A:middle
Why? Because we do not
actually cut through the object.

00:15:56.836 --> 00:15:58.316 A:middle
It's a phantom section.

00:15:58.466 --> 00:16:03.206 A:middle
We pretend that it along
this position of the plane

00:16:03.546 --> 00:16:06.156 A:middle
which ones are empty,
which ones are solid.

00:16:06.956 --> 00:16:10.446 A:middle
And that's what we do by
adding the sectional views.

00:16:11.136 --> 00:16:13.726 A:middle
There's a couple of
reasons for doing this.

00:16:14.026 --> 00:16:19.096 A:middle
One is you notice here if we do
the regular cutting section here

00:16:19.646 --> 00:16:23.536 A:middle
and remove the part, this detail
here, this hidden line here

00:16:23.536 --> 00:16:26.386 A:middle
which corresponds to this
hole is actually a hole

00:16:26.386 --> 00:16:30.356 A:middle
that is stored at the front part
of the object not in the back.

00:16:30.356 --> 00:16:33.276 A:middle
So we remove this
entire half here

00:16:33.276 --> 00:16:37.146 A:middle
in the front we will
lose this detail here

00:16:37.256 --> 00:16:40.086 A:middle
or this hole in the front.

00:16:40.256 --> 00:16:43.326 A:middle
So instead of doing
a regular section

00:16:43.466 --> 00:16:47.906 A:middle
like we just do a phantom
section along this position here

00:16:48.536 --> 00:16:50.926 A:middle
which parts in the
front view are empty.

00:16:50.926 --> 00:16:52.076 A:middle
So this parts empty.

00:16:52.526 --> 00:16:53.726 A:middle
From here to here solid.

00:16:53.726 --> 00:16:56.396 A:middle
And this one here
is empty again.

00:16:56.966 --> 00:17:00.456 A:middle
Okay? And from here to here is
solid again and this one here,

00:17:00.456 --> 00:17:02.816 A:middle
along this plane is empty again.

00:17:03.236 --> 00:17:06.386 A:middle
So what we did is we simply
added the section lines

00:17:06.766 --> 00:17:10.666 A:middle
without changing any of the
hidden lines to solid lines.

00:17:11.366 --> 00:17:15.186 A:middle
In other cases, phantom
section is really --

00:17:15.756 --> 00:17:17.316 A:middle
you can think of it
as an after thought.

00:17:17.376 --> 00:17:21.136 A:middle
You have the regular front
view, or the regular views

00:17:21.136 --> 00:17:24.096 A:middle
and then you realize, oh I
have a lot of hidden lines.

00:17:25.076 --> 00:17:27.766 A:middle
But I do not really want
to change everything

00:17:28.296 --> 00:17:30.206 A:middle
into a regular section.

00:17:30.206 --> 00:17:32.946 A:middle
So I'm just going to help
my audience by indicating

00:17:32.946 --> 00:17:37.596 A:middle
which areas along this cutting
plane are solid and hidden

00:17:37.596 --> 00:17:40.306 A:middle
by adding the section lines

00:17:40.926 --> 00:17:43.686 A:middle
without changing any
of the hidden lines.

00:17:43.966 --> 00:17:48.746 A:middle
So phantom section looks
exactly like a regular view,

00:17:49.576 --> 00:17:54.136 A:middle
regular multiview except you
add additional information

00:17:54.136 --> 00:17:57.696 A:middle
by indicating which parts
of the object are solid

00:17:58.466 --> 00:18:00.006 A:middle
by adding section lines.

00:18:00.776 --> 00:18:03.976 A:middle
So the original hidden
lines were kept.

00:18:04.506 --> 00:18:07.496 A:middle
Another type of section
is a broken-out section

00:18:07.496 --> 00:18:09.356 A:middle
and here's an illustration.

00:18:09.756 --> 00:18:13.596 A:middle
So instead of taking
a cutting section

00:18:13.596 --> 00:18:15.156 A:middle
through the whole
thing that slices.

00:18:15.946 --> 00:18:18.676 A:middle
A cutting plane that
slices this whole thing,

00:18:19.276 --> 00:18:21.676 A:middle
we just take a broken-out
section here.

00:18:21.796 --> 00:18:23.336 A:middle
So we're simply interested

00:18:23.336 --> 00:18:25.376 A:middle
in exposing the details
around this area.

00:18:26.466 --> 00:18:29.786 A:middle
So the break line, the
jagged edge here corresponds

00:18:29.916 --> 00:18:33.326 A:middle
to, separates areas
that were sectioned

00:18:33.326 --> 00:18:34.636 A:middle
from the un-sectioned parts.

00:18:34.966 --> 00:18:37.416 A:middle
Take note that there's no
need to do the cutting plane.

00:18:37.706 --> 00:18:41.066 A:middle
All right because it's obviously
really where the position

00:18:41.066 --> 00:18:43.076 A:middle
of the cutting plane is --

00:18:43.556 --> 00:18:46.256 A:middle
that you're trying to
use to expose the details

00:18:46.256 --> 00:18:47.516 A:middle
in the broken-out section.

00:18:48.056 --> 00:18:51.686 A:middle
A revolved section, okay, is --
here's a nice illustration here.

00:18:52.286 --> 00:18:55.996 A:middle
Okay. So instead of creating a
regular section, here's --

00:18:56.036 --> 00:18:59.876 A:middle
I can look at it from the top
view and then in the front view.

00:19:00.316 --> 00:19:03.836 A:middle
So instead of creating a right
side view, okay, to the right

00:19:03.956 --> 00:19:05.856 A:middle
like where my laser pointer is.

00:19:06.166 --> 00:19:08.106 A:middle
Okay. As a separate section --

00:19:08.456 --> 00:19:09.876 A:middle
sectional view to the right

00:19:09.876 --> 00:19:14.706 A:middle
of the front what we do is along
this cutting plane we are going

00:19:14.706 --> 00:19:18.136 A:middle
to expose the details
by taking the section

00:19:18.166 --> 00:19:22.036 A:middle
and then revolving it or
rotating it by 90 degrees.

00:19:22.966 --> 00:19:27.146 A:middle
So that this "T" here
okay is actually showing right

00:19:27.146 --> 00:19:28.116 A:middle
where the front view is.

00:19:28.116 --> 00:19:30.166 A:middle
Where it's rotated, 90 degrees.

00:19:30.236 --> 00:19:34.696 A:middle
So we revolve the cross section
view 90 degrees about an axis

00:19:34.936 --> 00:19:37.166 A:middle
and the visible lines,
right here,

00:19:38.596 --> 00:19:41.946 A:middle
right next to the revolved
section can be drawn as out --

00:19:42.606 --> 00:19:46.336 A:middle
or as indicated drawing
out could be broken-out.

00:19:47.016 --> 00:19:49.796 A:middle
The axis of revolution is drawn

00:19:49.836 --> 00:19:52.616 A:middle
on the revolved view
as a center line.

00:19:53.276 --> 00:19:57.426 A:middle
Removed section, okay, it's very
similar to the revolved section.

00:19:57.766 --> 00:20:00.556 A:middle
Okay. Except instead of
revolving it in place

00:20:00.556 --> 00:20:03.516 A:middle
and putting it there, it's
actually removed from the view

00:20:03.516 --> 00:20:04.856 A:middle
so you want it to be clear

00:20:05.196 --> 00:20:08.346 A:middle
and you create it right
to the right of it.

00:20:08.416 --> 00:20:12.376 A:middle
And take note that we only
show the details of the section

00:20:12.376 --> 00:20:13.686 A:middle
that you're trying to expose.

00:20:13.986 --> 00:20:17.096 A:middle
Okay? So the cross section
is then draw adjacent

00:20:17.096 --> 00:20:18.106 A:middle
to the orthographic view.

00:20:18.106 --> 00:20:20.886 A:middle
So we, in this case,
here's the slice

00:20:20.886 --> 00:20:23.246 A:middle
and we just show
the removed section.

00:20:23.316 --> 00:20:24.746 A:middle
Remove it from the
current position

00:20:24.746 --> 00:20:26.656 A:middle
and put it to the right of it.

00:20:27.676 --> 00:20:30.266 A:middle
And it's used when
there's not enough room

00:20:30.266 --> 00:20:34.526 A:middle
for the regular orthographic
view for a revolved section.

00:20:34.846 --> 00:20:38.376 A:middle
So if this gets too
cluttered here, too clouded,

00:20:38.786 --> 00:20:42.206 A:middle
instead of doing a revolved
section where you --

00:20:42.206 --> 00:20:44.446 A:middle
where this is, it's
going to get confusing,

00:20:44.446 --> 00:20:47.896 A:middle
we just take the regular
front view and just --

00:20:47.956 --> 00:20:51.966 A:middle
this part of the section we
just remove and show it --