chapter 08 orthographic convention
DESCRIPTION
technical drawingTRANSCRIPT
![Page 1: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/1.jpg)
Chapter 8
Convention Practicein Orthographic
Writing
![Page 2: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/2.jpg)
TOPICS Definition
Purposes
Types of conventions- Alternate position of side view
- Incompleted view
- Aligned view
- Enlarged view
- Non-existing intersection line
- Cylinder intersection
![Page 3: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/3.jpg)
DEFINITION
Convention is a commonly accepted practices
which disregard some strict rules of orthographic
projection.
Projection’ s
rules
ObjectMore readable
multiview
representation
Multiview
representation
Convention
practices
Disregardsome rules
![Page 4: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/4.jpg)
Using a dash line for
representing the hidden edge.
EXAMPLE : Already met convention practice
Front view
CONVENTIONPRACTICE
![Page 5: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/5.jpg)
PURPOSES
To improve the clarity of a drawing.
To reduce the drafting effort.
To save or efficiently use a drawingspace.
To facilitate the dimensioning.
![Page 6: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/6.jpg)
1. Alternate position of side view
2. Incompleted view
TYPES OFCONVENTION PRACTICE
2.1 Incompleted side view
2.4 Local view
2.3 Half view
2.2 Partial view
![Page 7: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/7.jpg)
3. Aligned view
4. Enlarged view
6. Intersection : Hole on a cylinder
5. Non-existing intersection line
TYPES OFCONVENTION PRACTICE
![Page 8: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/8.jpg)
ALTERNATE POSITION OF
SIDE VIEW
ALTERNATE POSITION OF
SIDE VIEW
![Page 9: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/9.jpg)
Whenever the height of an object is small and the
depth is relatively large, places the side view beside
the top view.
To save drawing space.
To improve the clarity of a drawing.
Purposes
Conventional practice
ALTERNATE POSITION OF SIDE VIEW
![Page 10: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/10.jpg)
Front
Top
Right
Example
![Page 11: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/11.jpg)
Example
Slot becomesmore readable.
Hole becomesmore readable.
New orientation of views stillagree with 3rd angle system.
![Page 12: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/12.jpg)
INCOMPLETED SIDE VIEWINCOMPLETED SIDE VIEW
![Page 13: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/13.jpg)
Incompleted side views are side views that
are eliminated a feature that can not clearly
seen from a selected viewing direction.
DEFINITION
![Page 14: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/14.jpg)
Principal view
Difficult to read and to dimension.
Left-side view Right-side view
Details are interfered by those
on the opposite view.
Example : Strictly orthographic projection.
![Page 15: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/15.jpg)
Example : Incompleted side views
Incompletedleft-side view
Incompletedright-side viewPrincipal view
Better describe an object and
facilitate dimensioning.
![Page 16: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/16.jpg)
Principal view
Example : Incompleted side views representation
![Page 17: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/17.jpg)
PARTIAL VIEW
HALF VIEW
LOCAL VIEW
PARTIAL VIEW
HALF VIEW
LOCAL VIEW
![Page 18: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/18.jpg)
Partial view is a view that represents portions
of the part that have a features need to clarify.
DEFINITION
Half view is a partial view that is illustrated only
half of the part.
Local view is a view that shows only features
need to clarify.
![Page 19: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/19.jpg)
Clearly seena shape.
Example : Partial views
![Page 20: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/20.jpg)
Symmetry symbol
Left half Right half
Thin line (4H)
Center line acts as aline of symmetry.
No continuous line !
Example : Half view
![Page 21: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/21.jpg)
Half view can be made by drawing the views
slightly beyond the line of symmetry.
No symmetry symbol.
It is allow for writinga break line.
In this course, we omit the break line.
Example : Half view : alternative representation
Thin line (4H)
![Page 22: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/22.jpg)
Example : Half view : two symmetry axes
![Page 23: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/23.jpg)
Example : Local view
Shape of theslot is completelyshown.
R67
Easy fordimensioning
![Page 24: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/24.jpg)
ALIGNED VIEWALIGNED VIEW
![Page 25: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/25.jpg)
DEFINITION
Align view is a view that is drawn by imaginarily
rotating the object’s features, appeared in a
principle view about symmetry axis.
![Page 26: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/26.jpg)
Example : Necessity of align view
Waste of time
Confuse
Apply
convention
Clear
Strictly Projection
![Page 27: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/27.jpg)
CONVENTION PRACTICE
For an object that has symmetrical positioned
features, it is advisable to show them on adjacent
view in true size at true radial distance from
the symmetry axis.
![Page 28: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/28.jpg)
Example : Align view of holes
Gives the impression that there
is a hole at the center of the plate.
Given
Apply
aligned
convention
![Page 29: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/29.jpg)
Example : Align view of holes
Given
Gives the impression that holes
are at unsymmetrical position.
Apply
aligned
convention
![Page 30: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/30.jpg)
Example : Align view of holes
Apply
aligned
convention
![Page 31: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/31.jpg)
Example :Example : Align view of ribs
Apply
aligned
convention
![Page 32: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/32.jpg)
Example : Align view of ribs & holes
Apply
aligned
convention
![Page 33: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/33.jpg)
Example : Align view of ribs & holes & keyway
Make Orthographic Projection
Apply Convention
![Page 34: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/34.jpg)
Example : Align view
![Page 35: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/35.jpg)
ENLARGED VIEWENLARGED VIEW
![Page 36: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/36.jpg)
Enlarged view is a view partly selected from
full view and is drawn with a larger scale.
DEFINITION
At full view, the selected portion is framed by
continuous thin line and having a name.
For an enlarged view, it must be specified both
name and scale used.
Conventional practice
![Page 37: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/37.jpg)
Example : Enlarged view
Full view
A
A (3:1)
Enlarged view
A (3:1)
or
Referenceposition
Scale
![Page 38: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/38.jpg)
NON-EXISTING LINE OF
INTERSECTION
NON-EXISTING LINE OF
INTERSECTION
![Page 39: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/39.jpg)
Non-existing line of intersection is the line of
intersecting surfaces that are eliminated by fillets
and rounds.
Non-existing line of intersection is the line of
intersecting surfaces that are eliminated by fillets
and rounds.
When true projection mislead the representation
of an object, it is necessary to show the additional
lines that are projected from the actual intersection
of the surfaces as if the fillets and rounds were
not present.
DEFINITION
Conventional practice
![Page 40: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/40.jpg)
Example : Non-existing line of intersection
Object does not has
rounds and fillets
Edges of the surfaces
are shown as lines in
the top view.
![Page 41: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/41.jpg)
Example : Non-existing line of intersection
The view looks like a plate
with a hole !!
Object has
rounds and fillets
No edge !
(No intersection between surfaces)
Convention practice required !
Construct a non-existing line of
intersection.
![Page 42: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/42.jpg)
Example : Non-existing line of intersection
![Page 43: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/43.jpg)
INTERSECTION BETWEENFILLET AND ROUND
Runout
![Page 44: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/44.jpg)
INTERSECTION BETWEENFILLET AND ROUND
![Page 45: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/45.jpg)
Tangent point
TO DRAW A RUNOUT
about 1/8 of circle
R
R/3
R = radius of fillet or round
R
![Page 46: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/46.jpg)
INTERSECTION BETWEENROUND PLANE SURFACE
![Page 47: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/47.jpg)
INTERSECTIONINTERSECTION
![Page 48: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/48.jpg)
HOLE IN CYLINDER
Large hole : True projection
![Page 49: Chapter 08 Orthographic Convention](https://reader036.vdocuments.mx/reader036/viewer/2022081506/55cf98eb550346d0339a718c/html5/thumbnails/49.jpg)
HOLE IN CYLINDER
Large hole : True projection Small hole : Convention