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St Margaret’s Academy. Graphic Communication. Sectional Elevations. CDT Department. Sectional Elevations. Used to show the insides of an object by drawing it as if it had been chopped. Will appear in the General and Credit exams. Read on to find out how!!!. Sectional Elevations.
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St Margaret’s Academy Graphic Communication Sectional Elevations CDT Department
Sectional Elevations • Used to show the insides of an object by drawing it as if it had been chopped. • Will appear in the General and Credit exams. • Read on to find out how!!!
Sectional Elevations Thickness of flower pot Plan The hidden detail lines on the elevation show the wall thickness of the flower pot. Elevation
Sectional Elevations Imagine taking a bite from a Mars Bar. What you would see is the soft bit, the caramel and the chocolate. This is what you would draw of the flower pot, what’s left after sectioning it. Mars being cut What you would see
X X Sectional Elevations The biting or cutting line is marked on the drawing using a line like the one below. It is called a cutting plane. Plan Notice the line has thicker lines at the 2 ends. Also notice the way the arrows point. This is the direction you will view the object when drawing the section. The letters XX is the name of the sectional cut Elevation
X X Sectional Elevations This is how the cutting plane would appear on the drawing. Plan Elevation
X X Sectional Elevations This is what would be drawn showing the thickness of the flower pot and the back curve of the top of the pot. Plan Elevation Sectional Elevation on XX
Sectional Elevations • Hatching is the name given to 45° lines that are used to show that a material is being cut. • The final touch to the sectional drawing is adding something called hatching. • Different materials or parts of the object are hatched using different styles of hatching. • The example below shows a pencil correctly hatched with lines in opposite directions for the lead and wooden parts. Pencil Lead Surrounding Wood
X X Sectional Elevations There is only one material in this example so only one direction of hatching. You should make sure there are equal spaces between your hatching lines. Plan Elevation Sectional Elevation on XX
Sectional Elevations • A bath plug is shown. We will be drawing a sectional elevation of the bath plug over the next few slides.
Sectional Elevations The Elevation of the bath plug is given. X You have to draw the plan and the sectional end elevation on XX. X
Sectional Elevations To draw the plan project the centre line up vertically. Mark on another centre line for the centre of the circle. X X
Sectional Elevations The plug is circular in shape. Therefore the plan can be drawn using a compass. Use your compass to draw the outline of the plug and the top of the plug. X X
Sectional Elevations The plug has the part that fits into the plug hole below the larger circle. This means that when you look at the plug from above you cannot see these parts. These are drawn using hidden detail lines. An example of a hidden detail line is shown below. It has evenly spaced short dashes. X X
Sectional Elevations We now have to show the hole through the top part. As this is hidden from view it is shown as hidden detail. X X
Sectional Elevations Now we will draw the sectional end elevation on XX. X X
Sectional Elevations Now we will draw the sectional end elevation on XX. Draw the ground line horizontally across from the elevation. X X
Sectional Elevations Draw the bounce line from the top right hand corner of the elevation. X X
Sectional Elevations Now project horizontally to the bounce line the widths on the plan. Then project them down vertically. X X
Sectional Elevations Now we will project all of the heights from the elevation across horizontally. X X
Sectional Elevations Now we will darken in the outline of the sectional End Elevation on XX. X X
Sectional Elevations This is the outline of the sectional End Elevation on XX without any construction lines showing. X X
Sectional Elevations Now we need to add hatching lines to show where the material of the object is cut. X X
Sectional Elevations These areas of the sectional drawing are fresh air. This means that they are not hatched. X X
Sectional Elevations There would be a hidden detail line drawn here on a normal end elevation drawing. However, on a sectional view, hidden detail is not shown. X X
Sectional Elevations Hatch the sectional view. X X