En Iso 13920-bf ›

| Nominal Dimension Range | Linear Tolerance (± mm) | |------------------------|------------------------| | Up to 30 mm | 0.5 mm | | 30 – 120 mm | 0.8 mm | | 120 – 400 mm | 1.2 mm | | 400 – 1000 mm | 2.0 mm | | 1000 – 2000 mm | 3.0 mm |

"Flatness of mounting pad: 1mm per 500mm (EN ISO 13920-BF)." en iso 13920-bf

Under Class B, the permissible deviations are calculated based on the length of the feature. For example, a general guide for Class B deviations might look like this (simplified for illustration): | Nominal Dimension Range | Linear Tolerance (±

Let’s get practical. Under :

Most common class for general engineering and steel construction. Medium (Mean) Straightness, Flatness, Parallelism en iso 13920-bf