Represents the tolerance class for geometrical features (such as straightness, flatness, and symmetry). The "k" is the medium classification for geometry.
Defines the tolerance class for linear and angular dimensions (Medium).
Together, tells the manufacturer: "For any dimension on this drawing that doesn't have a specific tolerance next to it, use the 'Medium' dimensional class and the 'K' geometrical class." 2. ISO 2768-1: Linear and Angular Dimensions (The 'm') general tolerance iso 2768-mk
Among its various classifications, is the most widely specified standard in precision machining, sheet metal fabrication, and general engineering. Here is a comprehensive breakdown of what ISO 2768-mK means, its specific tolerance limits, and how to apply it effectively. Decoding "ISO 2768-mK"
By utilizing this dual-classification system, a single note in the drawing block eliminates hundreds of redundant tolerance callouts, drastically improving drawing readability. 2. Linear and Angular Tolerances (Class m) Together, tells the manufacturer: "For any dimension on
| Nominal Size Range (mm) | Tolerance ‘k’ (mm) | | :--- | :--- | | Up to 100 | 0.1 | | >100 to 300 | 0.2 | | >300 to 1000 | 0.3 | | >1000 to 3000 | 0.4 |
Refers to ISO 2768-1 , which governs linear and angular dimensions (like lengths, radii, and diameters). or complex 3D-printed parts
Industries with strict regulatory frameworks typically demand tighter general tolerances (like ISO 2768-fH for fine precision) or complete custom tolerancing for every single feature. Best Practice Tip for Engineers
In mechanical engineering and manufacturing, specifying precise dimensions for every single feature on a technical drawing is highly inefficient. To streamline the design-to-manufacturing pipeline, engineers rely on general tolerance standards.
The lowercase represents the tolerance class for linear/angular dimensions (Part 1).
ISO 2768 was built primarily for metal removal (machining) and sheet metal fabrication. For highly flexible plastics, rubbers, or complex 3D-printed parts, standard machining tolerances may be unachievable or irrelevant.