lec8

Lecture 8: Section View ENGR 0101-04

Engineering Graphics

Spring 2018

Section View

Section View

Cutting line, It cuts out an object like a knife

The arrow shows the direction Of the knife

Section View Cross section, it means if your cutting line cut through an object, what will you see.

Section View Now use the same object, but change the cutting line’s direction

Section View

Although it is the same figure, the cross section Can be different due to the cutting line.

Section View

Section View The cross section can be a huge different Like it can be square or triangle

Section View Here is the cutting line and Its direction

Here is the cross section

Hatched area mean it is solid area

Empty area beam it is A hollow area (a hole, gap, or extremely thin area)

Section View Here is how cut section work in Architect field

Section View

Kind of hard to see because all Lines are hidden line

Section View

Section View

Cutting line

Cross section shows Where is the solid and Empty part

Section View

Section View

Section View Hatch line can be varies to show different material If you are not sure what to use, you can always use The general one

Section View

Section View

Section View

Section View

Section View

Just shows part of the cross section, And keep the object’s general looking

Section View

Section View

section1 section2 Section 3

The cutting line can be offset. If you see this case, just do each section by parts. And then combine them together to get your cross section view

The cutting line is offset doesn’t mean you need to have any line here. Keep it in one complete face

Section View

Section View

Section View pratice

Section View pratice First step, draw a line that represent the length of the cutting line.

The cutting line that touch the object is 7 unit

Therefore, draw a 7 unit line in your paper

Section View pratice Next step, label each “event” in the cutting line

Whenever the cutting line meet the object, something must happen. The interception is called “event”

Section View pratice Next step, label each “event” in the cutting line

In this example, there are 8 events

event1

event2

event3

4

5

6

7 8

Section View pratice Next step, label each “event” in the cutting line

event1

event2

event3

4

5

6

7 8

Also label the event in your paper

Section View pratice Next step, label each “event” in the cutting line

event1

event2

event3

4

5

6

7 8

Make sure each event are separate in respected distance

Section View pratice 3rd step: analyze how far each event goes

Let start with event 1, we start at 0 unit, and then goes up to 1 unit

Event1 start at unit 0, and then goes up by 1 event1

Section View pratice 3rd step: analyze how far each event goes

Between event 1 and 2, no event happen, so use a horizontal line to represent it

event1

event2

Section View pratice 3rd step: analyze how far each event goes

In event 2, it goes up by 2 unit

Event2 start here, which is where event 1 ended

event2

Section View pratice 3rd step: analyze how far each event goes

So, in your paper, goes up by 2

Event2 start here, which is where event 1 ended

event2

Section View pratice 3rd step: analyze how far each event goes

Between event 2 and 3, nothing happen

event2

event3

Section View pratice 3rd step: analyze how far each event goes

Event 3 is the parallel line that across the entire object

event1

event2 4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

If you draw a line to the left view, you can see the parallelogram is the thin rectangle that created by the hidden line.

event1

event2 4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

Event 3 goes “down” by 0.5 unit

event1

event2

event3 Event3 start where event 2 end, and then go down by 0.5

Section View pratice 3rd step: analyze how far each event goes

Again, nothing happen, so horizontal line to event 4

event1

event2

event3

4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

Event 4, and event 5 are obviously a hole

event3

4

5

Section View pratice 3rd step: analyze how far each event goes

And the hole goes 2.5 unit to the back, which is all the way to the start point

event3

4

Event 4 start

Section View pratice 3rd step: analyze how far each event goes

Nothing happen between 4 and 5

event3

4

5

Section View pratice 3rd step: analyze how far each event goes

Event 5 goes 2.5 unit up

event3

4

5

Section View pratice 3rd step: analyze how far each event goes

Horizontal line from 5 to 6

event3

4

5

Section View pratice 3rd step: analyze how far each event goes

Event 6 are the same parallelogram

event1

event2

event3

4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

Which is 0.5 unit, but this time we go up

event1

event2

event3

4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

6>7, same

event1

event2

event3

4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

In event 7, it is same shape as event2, but this time is on the other side

event1

event2

event3

4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

Event 7, goes down by 2

event1

event2

event3

4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

Event 7>8, same

event1

event2

event3

4

5

6

7 8

Section View pratice 3rd step: analyze how far each event goes

Event 8, 1 unit back

event1

event2

event3

4

5

6

7 8

Section View pratice 4th step: close out the boundary (optional)

In this example, there are a lot of open gaps, we need to consider if it needs to close it out

event1

event2

event3

4

5

6

7 8

Section View pratice 4th step: close out the boundary(optional) For example, between event 1 and 2, you can see the edge of the half circle in the background, then you can consider add it to your drawing

event1

event2

event3

4

5

6

7 8

Section View pratice 4th step: close out the boundary(optional)

Similar to event 7 and 8

event1

event2

event3

4

5

6

7 8

Section View pratice 4th step: close out the boundary(optional)

However, if you look and event 3 and 6

there are nothing to block your sight

Something that will consider as the boundary

Section View pratice 4th step: close out the boundary(optional)

That mean your boundary will looks like this

there are nothing to block your sight

Something that will consider as the boundary

Section View pratice 4th step: close out the boundary(optional)

Which is very awkward, so no to this

there are nothing to block your sight

Something that will consider as the boundary

Section View pratice 4th step: close out the boundary(optional)

Keep it open like this

event1

event2

event3

4

5

6

7 8

Section View pratice 5th step: hatch the solid area

Before that, we know 1>2, 4>5, and 7>8 are holes/gaps

event1

event2

event3

4

5

6

7 8

Section View pratice 5th step: hatch the solid area

Therefore, just hatch the others

event1

event2

event3

4

5

6

7 8

Section View pratice 6th step: delete the marks

The event is just helping us to draw the figure, delete those after you finish

event1

event2

event3

4

5

6

7 8

Home work