Fits and tolerances
Pick a size and a fit to see the hole and shaft limits, and how much clearance or interference you’ll get. ISO 286, sizes up to 500 mm.
Common fits at 25 mm
| Fit | Type | Clearance (+) / interference (−) | Typical use |
|---|---|---|---|
| H9/d9 | Loose running | Wide clearance for slow, loose bearings, idler pulleys, rough parts. | |
| H8/f7 | Close running | Running fits on accurate machines at moderate speed: spindle and gearbox bearings. | |
| H7/g6 | Sliding | Parts that move and turn freely with little play: guides, spigots, slide valves. | |
| H7/h6 | Locational clearance | Snug fit that still assembles by hand: locating spigots, gears on shafts. | |
| H7/k6 | Transition | Accurate location, light tap to assemble: couplings, bearing inner races. | |
| H7/n6 | Transition, tight | Firmer location, press or mallet: gears and pulleys with keys. | |
| H7/p6 | Light press | Interference for parts that must not move: bushes, dowels, bearing housings. |
Capital letters are holes, lower case are shafts. The number is the IT grade: smaller means tighter. Values per ISO 286-1 and 286-2; 1 µm = 0.001 mm. Printable version: ISO fits and tolerances chart (A3 PDF).
A guide only. These tools and figures are general starting points, not a guarantee for your job. Results depend on your machine, setup, material and tooling, so always check against the tool maker’s data, and talk to a Teravin sales engineer to make sure it’s right for your application. Call +61 8 9345 2099 or ask us. See our terms of use.
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