1. SANTANA CAD DRAFTING - ADAPTED FR PLTW
SECTIONAL VIEWS
FITZGERALD

2. WHY SECTIONAL VIEWS ? SECTIONAL VIEWS HELP SIMPLIFY
Multiviews can be confusing, especially when there are lots of overlapping hidden lines
Sectional Views look inside and only show what we see – There are never hidden lines in a section view
You can use section views to dimension to what would be a hidden line in the principle view

3. SECTIONAL VIEWS
A sectional view is made by passing an imaginary cutting plane through the part. Then removing and exposing the interior details to view.
The location of imaginary cut is shown in the adjacent view with a cutting-plane line or in a pictorial w/ a short-break line.

4. Cutting-Plane Line
Darkest, thickest, closest line of all the lines from the Alphabet of Lines
Arrows point to the side of the part we keep
The Section View or a note referring where the section view can be found is immediately behind the arrows
Long dash, two short dashes, long dash

5. SECTIONAL LINING
or a hatch pattern is drawn on any surface that touches the cutting plane

6. SECTIONAL LINING
or cross hatch should be distinctive & is drawn at an angle that is neither parallel or perpendicular to object lines

7. HIDDEN LINES IN SECTIONING
The purpose of Section Views is to reveal the hidden lines – now that we see those lines, they are no longer hidden and become object lines
If there would or should be more hidden lines behind the cutting plane they are omitted for the sake of clarity.

8. SECTION LINES IN ASSEMBLY
When there is more then one part - assemblies should be shown at different angles to show that there are multiple parts

9. SYMBOLS FOR SECTION LINING
Sectional lining or cross hatch is a general symbol for material, Hatch patterns are material specific

10. SECTION DRAWINGS Can be orthographic & part of the working drawing
Or can be pictorial as
in an isometric

11. TYPES OF SECTIONS There are many types of section views, such as
FULL SECTION
HALF SECTION
BROKEN-OUT SECTION
REVOLVED SECTION
REMOVED SECTION
OFFSET SECTION
ALIGNED SECTION

12. FULL SECTION
A full section is generated by passing a cutting plane fully through an object and removing half of it to give a view of its internal parts

13. FULL SECTION

14. HALF SECTION
A half section is developed by passing the cutting plane halfway through the object, and a quarter of it is removed. The half section is used to show both internal and external features of an object in the same view. It is used primarily for symmetrical objects.

15. OFFSET SECTION
The path of the cutting plane is not straight. Rather, it conforms (using 90 turns) to the significant features.
Offset section is used to show interior features that can not be located with a single cutting plane

16. OFFSET SECTION

17. THREE OFFSET SECTIONS

18. REMOVED SECTION
When there is not enough room on the paper or when it makes better sense - the section view can be placed other then in the adjacent view behind the arrows of the CPL
It is important to clearly label the drawing & reference it behind/or alongside the arrows of the CPL and the page # if on a different page
A removed section can be described as a revolved section that has been removed from the view where it was revolved. It is preferably drawn in line with the axis of cut.

19. REVOLVED SECTION
Here the cutting plane is passed perpendicular to the object's long axis. The resulting section is then revolved 90° in place to reveal the cut section in true size. A revolved section is used to show the section contour of long object - pipe, beam or handle at desired location.

20. BROKEN-OUT SECTION
A broken-out section is formed by passing a cutting plane through only a small selected portion of the object and using the short break line w/out the CPL

21. ALIGNED SECTION
Here, some features are rotated to get a conventional revolution view

22. ALIGNED SECTION

23. CONVENTIONAL HOLE REVOLUTIONS
(Convention is a standard or acceptable way of doing something)

24. CONVENTIONAL RIB REVOLUTIONS

25. CONVENTIONAL SPOKE REVOLUTIONS

26. CONVENTIONAL LUG REVOLUTIONS

27. Today we covered: Why we use sectional views
To show the inside of a part for clarification
Components of sectional views
CPL, Section lining (or hatch) & notes
Linetypes for sectional views
CPL, section lining & NO HIDDEN LINES
Types of sectional views
Full, half, removed, offset & more