Lecture Engineering drawing and design - Lecture 4: Orthographic views and sectioning. The learning objectives for this chapter include: Prepare for DrE-3; additional features in multiview drawings: cutting plane, section, hatching, hidden feature; section views and section drawings: ribs, webs, assemblies, threads. | Design web Design web Objectives for today ME 1110 – Engineering Practice 1 Engineering Drawing and Design - Lecture 4 Prepare for DrE-3 Additional features in multiview drawings: » Cutting plane, Section, hatching, hidden feature Orthographic Views & Sectioning Section views and Section drawings » Ribs, webs, assemblies, threads Prof Ahmed Kovacevic School of Engineering and Mathematical Sciences Room C130, Phone: 8780, E-Mail: 1 Ahmed Kovacevic, City University London 2 Ahmed Kovacevic, City University London Design web Orthographic Projections Design web Orthographic Projection Properties Projection planes Definition: Orthographic projections are parallel projections that Horizontal, frontal, and profile Each projection plane is perpendicular to adjacent projection planes Preserve true relationship between features Views top, front, and right side Only use the views that are needed to represent the object The most descriptive view should be the front view Represented with dashed lines Views should be selected to minimize the use of hidden lines Parallel lines are drawn parallel The geometry is generally not distorted Parallel projectors Light from a point source at an infinite distance View from a distance through a telescope 3 Ahmed Kovacevic, City University London 4 Ahmed Kovacevic, City University London Detailed views Design web Angle projections Design web Third Angle Projection Associated with English units If English units are used assume third angle projection unless otherwise specified Include ANSI standard symbol First Angle Projection Associated with SI units (International System of units) 5 Ahmed Kovacevic, City University London 6 Ahmed Kovacevic, City University London Design web Sectioned Drawing Design web How to reveal hidden feature Definition: » A multiview technical drawing that reveals details about internal features by displaying the part .