CBSE Class 12 Engineering Drawing

CBSE class 12 Engineering Graphics Sample papers with solutions, past year question papers and notes for all important topics covering isometric projections of solids, machine drawing, drawing of machine parts, assembly drawing and dis assembly drawings, access study material free download in pdf, prepared based on latest guidelines, term examination pattern and blueprint issued by cbse and ncert

click below for class 12 Engineering Graphics sample papers, worksheets, syllabus, ncert cbse books, ncert solutions, multiple choice questions (mcqs), easy to learn concepts and study notes of all chapters

Important Practice Resources for Class 12 Engineering Drawing

Our study material is designed based on the latest pattern of Objective MCQs (20%) and Case-Based integrated questions. With our teacher-prepared practice sheets, you will master time management which is very essential for completing complex assembly drawings within the 3-hour limit. Access the most updated CBSE syllabus and marking schemes to ensure every line you draw contributes to a perfect 100 score in the exams. The examination consists of a 70-mark theory paper and a 30-mark practical.

Unit I: Isometric Projection of Solids (25 Marks)

  • Construction of isometric scale showing main divisions of 10mm and smaller divisions of 1 mm, also showing the leading angles. Drawing helping view/s such as triangles, pentagon, hexagon, etc., using isometric scale.
  • Isometric projection (drawn to isometric scale) of right regular solids such as cubes; prisms and pyramids (triangular, square, pentagonal and hexagonal); cone; cylinder; sphere; hemi-sphere; when they are kept with their axis (a) perpendicular to HP/VP (b) parallel to HP and VP both.
  • Combination of any two above mentioned solids keeping the base side parallel or perpendicular to HP/VP and placed centrally together (Axis of both the solids should not be given parallel to HP).
  • Important Notes: 1. Hidden lines are not required in isometric projection. 2. Indicate the direction of viewing.

Note for Students: This unit focuses on mastering the technique of drawing 3D objects using a specific isometric scale and understanding how to combine different geometric solids.

Unit II: Machine Drawing (45 Marks)

  • Drawing of machine parts: (i) Drawing to full size scale with instruments. Introduction of threads: Standard profiles of screw threads - Square, Knuckle, B.S.W., Metric (external and internal); Bolts – Square head, hexagonal head; Nuts – Square head, Hexagonal head; Plain washer, Combination of nut and bolt with or without washer for assembling two parts together.
  • Free-hand sketches: Conventional representation of external and internal threads; Types of studs – Plain stud, Square-neck stud, Collar stud; Screws (round head, cheese-head, 90° flat counter sunk-head, hexagonal socket head and grub-screw); Types of rivets – Snap head, Pan head (without tapered neck), Flat head, 60° countersunk flat head.
  • Assembly drawings and Dis-Assembly drawings: 1. Bearings: (i) Open-Bearing (ii) Bush-Bearing. 2. Rod-Joints: (i) Cotter-joints for round-rods (Sleeve and cotter joint) (ii) Cotter-joints for square rods (Gib and cotter-joint). 3. Tie-rod and Pipe-joint: (i) Turnbuckle (ii) Flange pipe joint.
  • Assembly/Dis-assembly rules: 1. In all Assembly drawings, half sectional front view will be asked. Side/End view or Top View/Plan will be drawn without section. 2. In all Dis-assembly drawings, only two orthographic views (one of the two views may be half in section or full in section) will be asked of any two parts only.
  • Sectional View Conventions: 3. (a) In all sectional views, hidden lines/ edges are not to be shown. (b) In all full views, hidden lines/edges are to be shown.

Note for Students: This comprehensive unit teaches professional industrial standards for representing mechanical components, including detailed assembly and disassembly techniques.