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Mastering Orthographic Projection and Sectional Views in TVEE Engineering Drawing For students in the Technical and Vocational Education Examinations TVEE track, engineering drawing is a core component of their assessment. Specifically, orthographic projections and sectional views present a significant challenge due to the high spatial visualization skills required. In this article, we explain the fundamentals of layout planning, projection angles, and hatching conventions to help you score high marks in your TVEE exams. 1. First-Angle vs Third-Angle Projections You must know which projection standard is requested in your exam question. First-Angle Projection European System: The object is placed between the observer and the plane of projection. The plan top view is drawn below the front elevation, and the left-side view is drawn on the right. Third-Angle Projection American System: The plane of projection is between the observer and the object. The plan is drawn above the front elevation, and the left-side view is drawn on the left. Exam Tip: Always draw the correct projection symbol the cone frustum representation in the title block of your drawing sheet. Omitting the symbol can lead to a penalty of 1 to 2 marks. 2. Laying Out Your Drawing Sheet Before your pencil touches the paper for the final drawings, you must plan your layout to ensure the views fit neatly. 1. Determine Overall Dimensions: Find the maximum length, width, and height of the object. 2. Calculate Spacing: Calculate the gap between views based on your drawing sheet size usually A3 or A2. Ensure the spacing is even and leaves enough room for dimensioning lines. 3. Use Construction Lines: Lightly sketch the bounding boxes for all views using a 2H pencil. Only proceed to draw the actual object outlines using an HB pencil once you are sure the layout is centered. 3. Hatching Conventions for Sectional Views Sectional views are used to show internal details of a complex component by "cutting" through it. Hatch Angle: Use a $45^\circ$ set square to draw thin, parallel lines on all cut surfaces. Spacing: Keep the spacing between hatch lines consistent typically 2mm to 3mm. What Not to Hatch: Do not hatch thin web sections, ribs, shafts, bolts, nuts, or keys, even if the cutting plane passes through them. Hatching these elements makes the drawing confusing. For more technical drawing guides and to share your CAD or manual drawing sheets for review, visit our TVEE Technical Science Community/c/tvee-technical-science or refer to the TVEE Board/boards/tvee for past past questions.