Section Views By Fabian Sifuentez Melinda Elizondo Christina

Section Views By: Fabian Sifuentez Melinda Elizondo Christina Nunez Juan Zapata

Sectioning Basics n n Section views are a vital aspect of design and documentation and are used to give clarity. These views use a technique that is based on passing an imaginary cutting plane, or datum, through a part in order to reveal interior features. Section views also refine the stages of engineering design in order to improve the communications and problemsolving process. Creating section views requires visualization and following certain standards and conventional practices.

Sectioning Cut n n n Here we see an object that seems to have a feature cylindrical feature going thru it. Though one may only speculate, at first, we can’t fully know what features this object has until a section view is presented. By applying the concept of section views we may place a cutting plane across the top to reveal any features the object might contain.

Sectioning Cut (cont’d) n After cutting from the plane, we reveal a feature going not only vertically through the object, but also another running horizontally.

Cutting Planes Lines u u u Cutting plane lines show where the cutting plane, or datum, passes through an object. These lines represent the edge view of the cutting plane and are drawn in the view or views adjacent to the section view. Cutting lines are used mainly for clarity to the viewer. As seen in the previous object, the cutting plane is in the line of sight of the viewer. The cutting plane lines for the object would be going at a 45 degree angle and have equal spacing. Many times, these lines are presented in isometric pictorials in order to show the different dimensions that are affected from the cut.

Arrows of Orientation l l l Here we see cutting planes with arrows pointing a certain direction. This informs the viewer the direction of the line of sight meant for the cut. We also see the use of cutting plane lines used to inform the viewer the location of the cutting plane. This is help for engineers in determining what section has what features.

Types of Section Lines As it is seen, cutting plane lines are added to a section view to indicate the surfaces that are cut by the imaginary cutting plane. The lines that result from these planes are section lines. There also guidelines that these lines follow such as: keeping at a 45 degree angle, being uniform, not being too close together, and having the linework ending at the boundaries of the area.

Correct & Incorrect Section View Lines • As you can see, the proper form for sectional viewing requires no hidden lines. This creates redundancy and confuses the viewer. • Also, showing the axes where needed is a must in order to reveal holes properly.

Section View Types n As you would think, there are many types of section views that are used on technical drawing for the reason that some objects would require a more appropriate section view. Some of the views listed are: 1)Full Section Views are made by passing the imaginary cutting plane completely through the object, much like the objects that have been presented earlier. With this view, the cutting plane, section lines, and internal features are shown from a full frontal view. 2)Half Section Views are created by doing almost exactly like a full section but with only a 90 degree cut as opposed to a 180 degree cut. 3)Broken-out Section Views are used only when a portion of the object needs to be sectioned. A break line separates the sectioned portion from the unsectioned portion of the view.

Section View Types (cont’d) 4) Offset Section Views are created by having a cutting plane that is bent at one or more 90 degree angles to pass through important features. These views are necessary when one or more features would not be seen with a straight cutting plane. 5) Auxiliary Section Views may be fully or partially shown. Parts of the object that are behind the auxiliary section are sometimes not show in order to improve the clarity. 6) Aligned Section Views are special types of orthographic drawings used to align certain features of parts in order to clarify them for easier representation.

Examples of Some Section Views • On the right, a broken section view shows the necessary features with a broken line to show it is not at an angle. A jagged line is used to show what part of the object has been cut. • As usual, the axes for holes that are present, are displayed any necessary hidden lines are presented as well to show features the broken line view does not.

Examples (cont’d) u On the right an object is being displayed in full auxiliary view. Although the part of the object that is parallel to the ground is seen in the view, it is optional to show it.

Examples (cont’d) Here, on the left, a half section view is seen with only a 90 degree angle cut to display all the features necessary. On the right, an aligned section view is seen where only a part that is congruent to its other parts is cut while the rest is sectioned.

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