Overview
ISO 1985:2015 - "Machine tools - Test conditions for surface grinding machines with vertical grinding wheel spindle and reciprocating table - Testing of the accuracy" - standardizes methods for verifying the geometric accuracy and finishing machining performance of general-purpose and normal-accuracy surface grinding machines with a vertical wheel spindle and reciprocating table. This fourth edition (2015) updates the 1998 version and references ISO 230-1 and ISO 230-7 for test methods, instrument accuracy, installation and warm-up procedures, and axis-of-rotation checks. The standard is limited to geometric accuracy verification and is not intended for operational checks (vibrations, abnormal noises, speeds, feeds, etc.).
Key technical topics and requirements
- Scope and exclusions
- Applies to manual and numerically controlled (NC) surface grinding machines with a vertical grinding wheel spindle and reciprocating table.
- Not applicable to machines with fixed or rotating tables or those having longitudinal traverse of the wheelhead.
- Covers only geometric accuracy (not machine operation or dynamic characteristics).
- Geometric and machining tests
- Defines tests for straightness, squareness, positioning, repeatability and machining accuracy (examples: G1–G12 geometric tests).
- Example tolerances given in the standard: straightness of table movement (X‑axis) - 0.01 mm for measuring lengths up to 1 000 mm (increase by 0.01 mm per additional 1 000 mm; maximum 0.025 mm); vertical Z-axis straightness example - 0.02 mm for 300 mm.
- Measurement practices
- Linear dimensions in millimetres; angular deviations primarily expressed as ratios (with microradians or arcseconds for clarification).
- Minimum applicable tolerance set at 0.005 mm.
- Measuring instruments listed are illustrative (linear displacement sensors, straightness artefacts, gauge blocks, optical instruments); instrument selection must meet uncertainty requirements per ISO 230-1.
- Procedural notes
- Machine levelling per manufacturer and ISO 230-1 recommended procedures.
- Testing sequence is flexible to facilitate fixturing and measurement.
- Use of software compensation requires mutual agreement with the supplier, must be declared in test reports, and axes must not be locked during tests.
- Terminology
- Axis designation and component terminology referenced to ISO 841:2001; multilingual equivalents provided in Annex B.
Practical applications and users
- Who uses ISO 1985:2015:
- Machine tool manufacturers (acceptance testing and factory verification)
- Quality and metrology engineers in grinding shops
- Inspection labs and third‑party test houses
- Purchasing and acceptance teams for machine-tool procurement
- Practical value:
- Standardizes acceptance tests and tolerances for surface grinding machines, enabling objective evaluation of straightness, squareness, positioning accuracy, and machining results to ensure flatness and surface quality of workpieces.
Related standards
- ISO 230-1:2012 - Test code for machine tools - Part 1: Geometric accuracy
- ISO 230-2 - Determination of accuracy and repeatability of NC axes
- ISO 230-7 - Geometric accuracy of axes of rotation
- ISO 841:2001 - Terminology and axis designation
Keywords: ISO 1985:2015, surface grinding machines, vertical grinding wheel spindle, reciprocating table, geometric accuracy, machining tests, tolerances, ISO 230-1, positioning repeatability.