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Test Code Standard
ISO 230 Standards Reference
The "Bible" of machine tool accuracy. A cheat sheet for the entire ISO 230 series, from Geometric Accuracy to Thermal Distortion.
Why ISO 230 Matters
When buying a high-end CNC machine (DMG Mori, Makino, Okuma), the acceptance tests are based on ISO 230. Lower-end builders often cite JIS B 6338 or VDI/DGQ 3441 because they are more "forgiving".ISO 230 is the gold standard for truth in accuracy.
ISO 230 Series Breakdown
| Standard | Title / Focus | Key Tests & Description | Primary Tool |
|---|---|---|---|
| ISO 230-1 | Geometric Accuracy | Straightness, Flatness, Squareness, and Parallelism of axes. Done under "No Load". | Granite Square, Level |
| ISO 230-2 | Positioning Accuracy | The "Big One". Determines Positioning Accuracy (A), Repeatability (R), and Backlash (B). | Laser Interferometer |
| ISO 230-3 | Thermal Effects | Measures axis drift due to environmental temperature changes and spindle heat generation. | Displacement Sensors |
| ISO 230-4 | Circular Tests | Dynamic contouring accuracy. Identifies servo mismatch, reversal spikes, and stick-slip. | Telescoping Ballbar |
| ISO 230-5 | Noise Emission | Sound pressure levels during operation. | Decibel Meter |
| ISO 230-6 | Diagonal Displacement | Volumetric accuracy check by moving along body diagonals (Body Diagonal Test). | Laser Tracer |
| ISO 230-7 | Rotational Axes | Geometric accuracy of rotary tables (A, B, C axes). Center of rotation error. | Test Arbor / Laser |
Deep Dive: ISO 230-2
Understanding A, R, and B values.
ISO 230-3 (Thermal)
Coming Soon: How to test thermal drift.