ICSE Class 9 Technical Drawing Applications Syllabus 2026-27

Technical Drawing Applications (Subject Code 65) is an elective subject offered under Group III of the ICSE Class 9 curriculum. It develops the ability to produce and interpret accurate technical drawings using instrumental and geometric methods — skills that underpin engineering, architecture, manufacturing, and design. The subject combines plane geometry, engineering curves, solid geometry, and practical drawing conventions into a rigorous and visually precise discipline.

The subject carries 200 marks in total: 100 marks for the theory paper (Section I: 40 marks compulsory short answers + Section II: 60 marks with choice) and 100 marks for school-based internal assessment (a drawing file of minimum 15 assignments plus 3D models).

Class IX note: The Class IX examination is school-conducted on the portion covered during the year. The Class X ICSE Board Examination covers the full combined Class IX and X syllabus.

Exam at a Glance

Aims

•       Understand the principles of instrumental drawing and acquire basic skills in traditional drafting techniques

•       Develop knowledge and proficiency in Technical Drawing as the precise graphical language of engineering and design

•       Develop the ability to visualise, represent, and interpret two-dimensional and three-dimensional objects

•       Apply conventions of plane geometry, engineering curves, solid geometry, oblique drawing, and orthographic/isometric projection

•       Develop proficiency in using drawing instruments: T-square, set squares, compass, divider, scales

•       Provide a foundation for further study in engineering, architecture, and technical design

Foundation: Drawing Conventions and Basics (Class IX)

Class IX students establish proficiency in the following before the ten main units:

Drawing Instruments

•       Drawing board; T-square (horizontal lines); set squares (45-45-90 and 30-60-90 triangles): uses and correct handling

•       Compass (circles and arcs); divider (measuring and transferring distances)

•       Drawing scales (1:1, 1:2, 1:5, 1:10, 2:1, 5:1): reading and using a scale accurately

•       Pencil grades (H, HB, 2H) for construction lines, outlines, dimension lines

•       Drawing sheet sizes (A0 to A4) and orientation

Types of Lines (IS Conventions)

Engineering Lettering and Sheet Layout

•       Upright capitals and small letters, single stroke, freehand; numerals uniform height; written between correct guidelines (5mm or 7mm)

•       Sheet layout: border lines at correct margins (25mm left for binding); title block at bottom right with student name, drawing title, date, scale, sheet number, class

Unit 1: Geometrical Constructions Based on Plane Geometry

All constructions with drawing instruments only (compass, ruler, set squares) — no protractor unless permitted.

Line and Angle Constructions

•       Perpendicular bisector of a line segment; dividing a line into equal or proportional parts

•       Perpendicular lines: from a point on the line; from a point outside the line

•       Parallel lines at a given distance

•       Bisector of an angle

•       Angles without a protractor: 30°, 45°, 60°, 90° and combinations (15°, 75°, 105°, 120°, 135°, 150°)

Triangle, Quadrilateral, and Polygon Constructions

•       Triangles: SSS, SAS, ASA, right-angled (hypotenuse + side), equilateral (side or altitude), isosceles

•       Quadrilaterals: square (side or diagonal), rectangle, rhombus (side + angle or diagonals), parallelogram, trapezium

•       Regular polygons inscribed in a circle and on a given side: pentagon, hexagon, heptagon, octagon; general method

Circle Constructions

•       Circle through three given points; centre of a given arc or circle

•       Tangent from an external point; tangent at a point on the circle; internal and external tangents to two circles

•       Inscribed and circumscribed circles about triangles and polygons

Unit 2: Area Constructions

•       Triangle to rectangle/parallelogram: constructing an equal-area rectangle or parallelogram from a given triangle

•       Rectangle to triangle: and other equivalent area transformations

•       Polygon to triangle: systematic reduction of sides to convert any rectilinear figure to an equal-area triangle

•       Reduction/enlargement of similar figures: constructing a figure similar to a given figure with a specified area ratio

Unit 3: Templates

•       Practical application of geometric constructions to produce templates (flat profiles used in engineering)

•       Transferring measures from a constructed scale to create scaled drawings: field drawings, templates, orthographic projections

•       Drawing templates for engineering shapes: gaskets, washers, flanges, and other flat profiles

Unit 4: Scales

•       Representative Fraction (RF): RF = drawing length / actual length; full size (1:1), reduction, and enlargement scales

•       Plain scale: represents two units (e.g. metres and decimetres); construction and use

•       Diagonal scale: represents three units using the principle of similar triangles (e.g. metres, decimetres, centimetres); construction and use

•       Comparative scale: two scales with different units for conversion (e.g. miles and kilometres)

•       Scale of chords: construction and use for measuring angles without a protractor

•       Reading a given scale; using it to measure and set out distances accurately

Unit 5: Engineering Curves

Conics (Conic Sections)

•       Ellipse — locus: sum of distances from two foci is constant. Construction methods: (i) arcs of circles/trammel method, (ii) concentric circles method, (iii) oblong/rectangle method, (iv) eccentricity method. Applications: arches, manhole covers

•       Parabola — locus: equidistant from focus and directrix. Construction methods: (i) rectangle method, (ii) tangent method, (iii) eccentricity method. Applications: reflectors, bridges, arches

•       Hyperbola — locus: difference of distances from two foci is constant. Construction: eccentricity method. Applications: cooling towers, gear profiles

Cycloidal Curves

•       Cycloid: point on a circle rolling along a straight line. Step-by-step plotting method

•       Epicycloid: point on a circle rolling OUTSIDE another circle. Application: gear tooth profiles

•       Hypocycloid: point on a circle rolling INSIDE another circle; when rolling circle diameter = half directing circle, it traces a straight line (diameter)

•       Involute of a circle: end of a taut string unwound from a circle. Application: involute gear tooth profiles. Construction: rolling line method

Unit 6: Solids -- Orthographic Projections

Principles of Orthographic Projection

•       First-Angle (European) Projection: object between observer and plane; views projected away from observer

•       Third-Angle (American) Projection: plane between observer and object; views projected toward observer

•       Projection planes: VP (Front View/Elevation), HP (Top View/Plan), PP (Side View/End Elevation); XY reference line

•       Correct layout in First-Angle: Top View below Front View; Side View to the right

Projections of Points, Lines, and Planes

•       Points: all four quadrants; finding elevation and plan from given position relative to reference planes

•       Lines: parallel to both planes; perpendicular to one plane; inclined to one plane; inclined to both planes — finding true length (TL); auxiliary elevation and plan

•       Planes: parallel to one RP; perpendicular to one and inclined to the other (finding true shape by auxiliary view); inclined to both

Projections of Solids

Right prisms, right pyramids, cylinder, and cone; base polygons up to six sides.

•       Axis perpendicular to HP (solid resting on base): all three views

•       Axis parallel to HP and perpendicular to VP: all three views

•       Axis parallel to HP and inclined to VP; axis inclined to HP and parallel to VP: two-view problems; auxiliary view if needed

•       Auxiliary plane: shown in question when required

Unit 7: Oblique Drawing

•       Cabinet oblique: receding lines at HALF their true length; receding axis at 30° or 45°. Less distorted than cavalier. Most commonly used in ICSE questions

•       Cavalier oblique: receding lines at FULL true length; receding axis at 30° or 45°

•       Drawing simple objects in oblique from orthographic views or dimensions

•       Circular features: true circles on the front face; approximated as ellipses on receding faces

•       Choosing the most suitable face for the frontal plane to minimise distortion

Unit 8: Sections of Right Solids

Finding the true shape of the cut face when a solid is cut by a cutting plane. Solids: right prism, right pyramid, cylinder, cone.

•       Cutting plane positions: perpendicular to axis (cross-section); inclined to axis; parallel to slant edge

•       True shape of section: found by auxiliary view; shown with 45-degree hatching

•       Cone sections: plane parallel to generator → parabola; inclined to base → ellipse; parallel to base → circle; perpendicular to base → hyperbola

•       Sectional elevation types: full section, half section (for symmetrical objects), offset section

Unit 9: Isometric Drawing

Principles

•       Isometric axes: one vertical + two at 30° to horizontal (120° to each other)

•       Isometric lines: parallel to any isometric axis are drawn to true length; non-isometric lines plotted between located end points

•       Isometric drawing: true measurements used (not the reduced isometric scale) for convenience

Drawing Solids in Isometric

•       Isometric drawing of prisms, cubes, pyramids, cylinders, and cones from given orthographic views or dimensions

•       Circles in isometric: four-centre ellipse method (approximation) for circles on each isometric face

•       Combinations of solids (e.g. cylinder on a rectangular block)

•       Converting between orthographic views and isometric drawing

Unit 10: Sectional Orthographic Views

•       Full section: cutting plane through entire object; section shown with hatching; hidden lines removed in the sectioned portion

•       Half section: for symmetrical objects; one quarter removed; half shows interior (sectioned), half shows exterior

•       Offset section: cutting plane stepped to pass through features not in a single line

•       Revolved section: cross-section rotated 90° and shown within the view; used for spokes, ribs, structural members

•       Removed section: cross-section placed adjacent to the main view

•       Hatching conventions: thin 45° parallel lines; adjacent parts in opposite directions or different angles; very thin sections shown solid

•       Constructing a sectional elevation from two orthographic views

Development of Surfaces

Unfolding the surface of a solid into a flat plane — used in sheet metal work, packaging, and manufacturing.

•       Right prism: lateral faces unfolded into a flat strip (rectangle x number of faces)

•       Right pyramid: triangular faces unfolded using slant edge true length

•       Right cylinder: rectangle; height = height of cylinder; width = circumference (π × diameter)

•       Right cone: sector of circle; radius = slant height; arc length = circumference of base

•       Truncated solids: development of prism, pyramid, cylinder, or cone cut by a cutting plane; cut section shown as a curve on the development

Internal Assessment (100 Marks)

Drawing File (Portfolio) -- Minimum 15 Assignments

•       At least 15 drawing assignments covering all units: line types, lettering, geometric constructions, scales, engineering curves (ellipse, parabola, cycloids, involute), orthographic projections, oblique drawing, sections, isometric, sectional views, surface developments

•       One or two assignments on half imperial size drawing paper (560mm x 380mm)

•       Each assignment: properly drawn title block; correct line weights and types; neat lettering; accurate construction

Three-Dimensional Models

•       3D model from stiff cartridge paper: fold and glue the surface development (net) to make a prism, pyramid, cylinder, or cone

•       Thermocol (expanded polystyrene) model: cut a truncated solid (truncated prism, pyramid, cylinder, or cone) to show the section plane and cross-section shape

Assessment Criteria

Preparation Tips for Students

For the Theory Paper

•       Technical Drawing is a skill — practise all constructions with instruments regularly; do not rely on approximate methods or sketching

•       Section I (short answers): be prepared for questions on any unit — naming line types, identifying projections, recognising curve types, reading scales, and identifying section types

•       Engineering Curves: know the locus-based definitions of ellipse, parabola, hyperbola, cycloid, epicycloid, hypocycloid, and involute; know at least two construction methods for the ellipse

•       Orthographic projections: practise all three views (front, side, top) of prisms, pyramids, cylinders, and cones in all required positions; project correctly from view to view using thin construction lines

•       Isometric drawing: practise the four-centre ellipse for circles on isometric faces; practise converting from orthographic views to isometric

•       Sections and developments: know when to use full, half, and offset sections; practise finding true shapes of sections and developing surfaces of all four standard solids

•       Always check: thick outlines, thin hidden lines, very thin centre/construction lines; 45-degree hatching, evenly spaced, not crossing features

For the Internal Assessment

•       Complete your drawing file throughout the year — do not leave all 15 assignments until the end

•       Each assignment: clean, fully dimensioned, correct title block, correct line types

•       For 3D models: measure the net accurately before cutting; edges should meet cleanly when folded

•       Practise setting up your board and instruments efficiently — speed and accuracy are both assessed