Search results
- Objects that are symmetrical about a centre line you may draw having one half as a multiview and the other half in section view. In such situation Cutting plane line is shown across the whole part; Section plane through center line of a symmetric part can be omitted; Hidden lines in half sections are usually omitted.
www.mcgill.ca/engineeringdesign/step-step-design-process/basics-graphics-communication/sectioning-techniqueSectioning Technique | Engineering Design - McGill University
People also ask
How to draw a symmetrical object with half sections?
What is a half section in drawing?
How do you draw a symmetrical object?
What is a half section view?
What is an example of a half section?
How to draw a sectional view?
A half section view means that you are only removing a quarter of an object. This type of view is ordinarily used when the object is symmetrical or if you only need to show a portion of a complex assembly.
- General Principles
- Section Lines and Symbols
- Cutting Planes
- Main Principles of Placement of Sectional Views
A sectional view represents the part of an object remaining after a portion is assumed to have been cut and removed.The exposed cut surface is then indicated by section lines.Hidden features behind the cutting plane are omitted, unless required for dimensioning or for definition of the part.Section lines, or hatching, that represent the cut surface usually consist of thin parallel lines, as shown below, drawn at an angle of approximately 45° to the principal edges or axes of the part. For most purposes, the general use symbol of cast iron is used. When it is desired to indicate differences in materials, for example on assembly drawing...
Cutting plane lines which show where the cutting plane passes through the object, represent the edge viewof the cutting plane and are drawn in the view(s) adjacent to the section view. Here the cutting plane is drawn as an edge in the top view, which is adjacent to the sectioned front view. This is a frontal cutting plane. Lines of sight should alw...
Whenever practicable, and except for revolved sections, you should project sectional views perpendicular to the cutting plane and place it in the normal position for third angle projection.You should never show the views in first angle projected position on a third angle projection drawing.When the preferred placement is not practical you may remove the sectional view to some other convenient position on the drawing, but it must be clearly identified, usually by two capital letters,...Normally, you should not change orientation of the view, but if this becomes necessary, you must state the number of degrees through which it is revolved.- Cutting Plane. A surface cut by the saw in the drawing above is a cutting plane. Actually, it is an imaginary cutting plane taken through the object, since the object is imagined as being cut through at a desired location.
- Cutting Plane Line. A cutting plane is represented on a drawing by a cutting plane line. This is a heavy long-short-short-long kind of line terminated with arrows.
- Section Lining. The lines in the figure above, which look like saw marks, are called section lining. They are found on most sectional views, and indicate the surface which has been exposed by the cutting plane.
- Full Sections. When a cutting plane line passes entirely through an object, the resulting section is called a full section Fig. 7 illustrates a full section.
- Full Sections. A Full section view is where the entire part or assembly is cut on a single plane. The generated section view that is created may form part of the same view as the reference view, permitted the correct projection method (first or third angled projection) is used.
- Half Section. The half section view may be used where a part or assembly is symmetrical about the centerline of the part or assembly. This will save space on the drawing with over population of reference and section views.
- Partial Section. A Partial section is used when only a certain portion of a part or assembly is cut in order to show important detail or geometry. The whole part or assembly is not sectioned as that may minimize the other information show.
- Revolved Section. A revolved section is a section that is made at a certain point in a part and revolved 90° to show the cross section of the part. The part can be broken to show the revolved section or the revolved section can be superimposed on the part itself.
Half section Half sections are useful when drawing a sym-metrical object. Both the inside and the out-side can be shown in one view. Use a centerline where the exterior and half-sectional views meet because the object is not actually cut. In the top view, show the complete object because no part is actually removed. If the direction of viewing is
HALF SECTIONS •If a cutting plane passes halfway through an object, the result is a half section. •Expose the interior and retain the exterior. •It is often used for symmetrical objects, not for detail drawings.
Draw the half-sectional views—obtained when the cutting plane cuts halfway through the object so that half of the object appears in section whereas the other half is the external view—for symmetrical objects. Draw revolved sections, removed sections, partial sections and offset sections.
