Holes, Fits & Tolerances calculators & charts

Clearance holes, ISO 286 hole and shaft limits, true position, press fits, O-ring glands and thermal growth: the tools that decide whether two parts actually go together. Limits follow ISO 286, the press-fit calculator uses the thick-walled cylinder (Lamé) equations to give interface pressure and press tonnage, and O-ring grooves follow the AS568 size series, so the tolerance on the drawing becomes a number you can measure at the machine.