When to use H7/n6
Almost always interference: press assembly. For bushes and gears held without other locking under moderate loads.
H7/n6 tolerances for every diameter
| Diameter (mm) | Hole H7 (µm) | Shaft n6 (µm) | Max clearance | Min clearance |
|---|---|---|---|---|
| ≤ 3 | +10 / 0 | +10 / +4 | +6 | -10 |
| 3–6 | +12 / 0 | +16 / +8 | +4 | -16 |
| 6–10 | +15 / 0 | +19 / +10 | +5 | -19 |
| 10–18 | +18 / 0 | +23 / +12 | +6 | -23 |
| 18–30 | +21 / 0 | +28 / +15 | +6 | -28 |
| 30–50 | +25 / 0 | +33 / +17 | +8 | -33 |
| 50–80 | +30 / 0 | +39 / +20 | +10 | -39 |
| 80–120 | +35 / 0 | +45 / +23 | +12 | -45 |
| 120–180 | +40 / 0 | +52 / +27 | +13 | -52 |
| 180–250 | +46 / 0 | +60 / +31 | +15 | -60 |
| 250–315 | +52 / 0 | +66 / +34 | +18 | -66 |
| 315–400 | +57 / 0 | +73 / +37 | +20 | -73 |
| 400–500 | +63 / 0 | +80 / +40 | +23 | -80 |
Negative clearance = interference: the shaft is larger than the hole. Values in micrometres (µm, thousandths of a millimetre). Diameter ranges: over the first value, up to and including the second.
Other fits
Values computed from the IT grades and fundamental deviations of ISO 286-1, checked against several published tables. For critical designs the standard itself is what counts.