Microsoft Word - lecnote_fm_engineering drawing

Half-Sections A half-section is a view of an object showing one-half of the view in section, as in figure 6.13 (a) and (b) (a) ( ...

The diagonal lines on the section drawing are used to indicate the area that has been theoretically cut. These lines are called ...

Usually hidden (dotted) lines are not used on the cross- section unless they are needed for dimensioning purposes. Also, some hi ...

Review questions Describe the purpose of sectioning in technical drawings What is “direction of sight” in sectioning? Mention t ...

CHAPTER SEVEN PROJECTION OF POINTS, LINES AND PLANES Objectives: At the end of the chapter, students should be able to: ♦ Discus ...

7.1. Introduction A major problem in technical drawing and design is the creation of projections for finding the true views of l ...

A point can be considered physically real and can be located by a small dot or a small cross. It is normally identified by two o ...

7.3. Projection of Point Since a point is a location in space and not a dimensional form, it must be located by measurements tak ...

Figure 7.1 Projection of a point 7.4. Lines in Space Lines can be thought as a series of points in space, having magnitude (leng ...

the end points of line 1-2 are denoted 1H and 2H in the horizontal views, 1F and 2F in the frontal view, and 1P and 2P in the pr ...

parallel. Since there are three principal planes of projection, there are three principal lines: horizontal, frontal and profile ...

and profile views and as a point view in the horizontal views. ♦ Level line: any line that is parallel to the horizontal plane i ...

7.4.2 Orthographic Projection Of A Line Lines are classified according to their orientation to the three principal planes of pro ...

In figure above, each end points of line 1-2 is located from two fold lines in each view, using dimensions or projection lines t ...

example (3), line1-2 is parallel to both the profile and horizontal projection planes and appears as a point view in the frontal ...

B. Inclined Lines Lines that appear true length in the frontal or profile view (but not both) are inclined Figure 7.6 Inclined l ...

C. Frontal Lines A line that is parallel to the frontal projection plane is a frontal line. Frontal lines are principal lines an ...

Line 1-2 lies behind the frontal plane the same distance in the horizontal and profile views, dimensions D1.Note that it is not ...

parallel to the profile view) it appears as a point views in the frontal view and true length in the profile view and is a combi ...

Figure 7.10 Orthographic projection of horizontal lines E. Profile Lines A profile line is parallel to the profile plane and sho ...