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Examples of Sections Views

Full Section View A full section view is made by passing the imaginary cutting plane completely through the object. As shown in figure 1, all the hidden features intersected by the cutting plane are represented by visible lines in the section view. Surfaces touched by the cutting plane have section lines drawn at a 45-degree angle to the horizontal.  Hidden lines are omitted in all section views unless they must be used to provide a clear understanding of the object. The top view of the section drawing shows the cutting plane line, with arrows pointing in the direction of line of sight to view the sectioned half of the object. In a multi-view drawing, a full-sectioned view is placed in the same position that an unsectioned view would normally occupy, I.e., a front section view would replace the traditional front view. Figure 1 shows a full section view of an object. Half Section view Half sections are created by passing an imaginary cutting plane only halfway through an object. Hid...

Projections on Auxiliary Planes  Sometimes none of the three principal orthographic views of an object show the different edges and faces of an object in their true sizes, since these edges and faces, are not parallel to any one of the three principal planes of projection.  In order to show such edges and faces in their true sizes, it becomes necessary to set up  additional planes of projection  other than the three principal planes of projection in the positions which will show them in true sizes.  If an edge or a face is to be shown in true size, it should be parallel to the plane of projection.  Hence the additional planes are set up so as to be parallel to the edges and faces which should be shown in true sizes.  These additional planes of projection which are set up to obtain the true sizes are called  Auxiliary Planes.  The views projected on these auxiliary planes are called  Auxiliary Views. The auxiliary view method may be appli...

Point in the Second quadrant Point P is 30 mm above HP, 50 mm behind VP and 45 mm in front of left PP. Since point P is located behind VP, the VP is assumed transparent.  The position of the point w.r.t the three planes are shown in Figure 1.  The direction of viewing are shown by arrows. After projecting the point on to the three planes, the HP and PP are rotated such that they lie along the VP. The direction of rotation of the HP  and PP is shown in figure 2. As shown in figure 3, after rotation of the PP and HP, it is found that the VP and HP is overlapping. The  multi-view  drawing for the point P lying in the second quadrant is shown in figure 4. Though for the projection of a single point, this may not be a problem, the  multi-view  drawing of solids, where a number of lines are to be drawn, will be very complicated. Hence second angle projection  Technic  is not followed anywhere  for engineering drawing. Figure 1. ...