Every fit falls into one of three categories based on the interaction between the hole and shaft tolerance zones.
: H7/p6 (light press), H7/s6 (medium drive fit for gear hubs). Fit Tolerance
: High-precision location where parts need to be snug but removable. Examples : H7/k6 (locational transition for dowel pins). 2. ISO 286 Notation System Every fit falls into one of three categories
The ISO 286 Standard uses an alphanumeric code (e.g., ) to define fits. ensuring a gap for movement.
: The tolerance zones overlap; the resulting fit could be a slight clearance or a slight interference depending on the actual manufactured size.
: Rotating shafts, sliding parts, or items that need easy hand-assembly.
: The shaft is always smaller than the hole, ensuring a gap for movement.