Overview
ISO 9962-2:1992 - "Manually operated draughting machines - Part 2: Characteristics, performance, inspection and marking" defines mandatory requirements for the design, performance verification and marking of manually operated draughting machines used in technical drawing. This part of the ISO 9962 series covers appearance and construction, functional performance, inspection methods and required marking information. Annex A specifies requirements for the inspection scale rule and inspection drawing board used in testing.
Key topics and technical requirements
- Scope: Requirements for appearance, construction, performance testing, inspection and marking of manually operated draughting machines.
- Construction & materials:
- Components must be made of sufficiently strong, rigid materials and manufactured with care.
- Coatings and surface treatments must resist colour change, peeling and rust.
- Graduations and markings:
- Protractor and vernier graduation lines and numbers must be clear, even and free of defects.
- Mechanical features:
- Secure fixing bracket, smooth-operating contact-adjusting screw, smoothly rotating scale rule mounting plate and secure attachment for scale rules.
- Controls such as reference line lever, indexing lever, angle lever, and horizontal/vertical brakes must operate smoothly, lock securely and be free from play or abnormal noise.
- Performance & inspection:
- Detailed measurement methods are prescribed, including use of an inspection drawing board and magnifier (typically magnification ≥ x5 and minimum vernier reading of 10′, or 5′ where applicable).
- Performance checks include accuracy of protractor/vernier, accuracy of indexing plate attachment, eccentricity of protractor graduations, accuracy of indexing divisions, parallel movement accuracy of scale rule, perpendicularity/parallelism of tracks and clearance between scale rules and drawing board.
- Typical permissible deviations include angular tolerances in minutes (e.g., 10′ or 5′) and linear tolerances of ±0.3 mm for various positional checks; maximum scale-rule-to-board clearance 0.3 mm.
- Marking:
- Equipment must be marked with the manufacturer’s name or trade mark, the designation per ISO 9962-1, and year and month of manufacture.
Applications and users
- Who uses it: draughting machine manufacturers, quality and compliance engineers, calibration and inspection laboratories, purchasers specifying equipment for technical drawing, and standards bodies.
- Practical value:
- Ensures consistent manufacturing quality and interchangeability of manual draughting equipment.
- Provides standardized inspection procedures and test fixtures (inspection scale rule and drawing board) to verify machine accuracy for engineering, architectural and technical drawing tasks.
- Useful when specifying procurement requirements, performing acceptance tests or maintaining drawing-room equipment.
Related standards
- ISO 9962-1:1992 - Definitions, classification and designation (referenced for terminology and designation).
- ISO 9962-3 - Dimensions of scale rule chuck plates (interfaces with mounting plate requirements).
- Prepared by ISO/TC 10 (Technical drawings, product definition and related documentation).
Keywords: ISO 9962-2, manually operated draughting machines, draughting equipment standards, inspection drawing board, scale rule, protractor accuracy, vernier, performance requirements, marking.