General Tolerance Iso 2768-mk Access

This article provides a detailed overview of the ISO 2768-mK standard, explaining its components, application, and importance in machining and fabrication. What is ISO 2768-mK?

Applicable to angles where no tolerance is shown.

These apply to external sizes, internal sizes, steps, diameters, and distances. All values are in millimeters (mm). Nominal Size Range (mm) Tolerance Class (Medium) over 3 to 6 over 6 to 30 over 30 to 120 over 120 to 400 over 400 to 1000 over 1000 to 2000 over 2000 to 4000 2. Broken Edges (External Radii and Chamfers) These apply to the rounding or beveling of sharp edges. Nominal Size Range (mm) Tolerance Class m (Medium) over 3 to 6 3. Angular Dimensions

Under ISO 2768-1, there are four tolerance classes: f (fine), m (medium), c (coarse), and v (very coarse). The class is the most frequently used in general mechanical engineering. Linear Dimensions (mm) general tolerance iso 2768-mk

Perpendicularity defines the allowable deviation from a perfect 90-degree angle between two surfaces. It is based on the longer of the two sides forming the angle. Nominal Length of Shorter Line (mm) Perpendicularity Tolerance Class K (mm) 100 to 300 300 to 1000 1000 to 3000 3. Symmetry

ISO 2768-1 uses four classes: (fine), m (medium), c (coarse), and v (very coarse). The "m" class is the most common industry standard for CNC machining and general metalwork. Nominal Dimension Range (mm) Tolerance for "m" Class (mm) ±plus or minus Over 3 to 6 ±plus or minus Over 6 to 30 ±plus or minus Over 30 to 120 ±plus or minus Over 120 to 400 ±plus or minus Over 400 to 1000 ±plus or minus Data sourced from standard ISO 2768-1 charts . ISO 2768-2: General Geometrical Tolerances (The "K")

For a nominal size (the dimension on the drawing), the permissible deviation under class is: Nominal Size Range (mm) Tolerance (± mm) Over 3 to 6 Over 6 to 30 Over 30 to 120 Over 120 to 400 Over 400 to 1000 Data sourced from ZEISS Quality Forum . External Radii and Chamfer Heights (mm) This article provides a detailed overview of the

If you are working with a (like plastics) that might require different tolerance considerations.

Using ISO 2768-mK is ideal for non-critical features of a part where "standard" workshop accuracy is sufficient. It allows machinists to work faster by focusing only on the dimensions that truly require high precision (e.g., press fits or bearing seats). Common Tolerance Ranges for "mK"

QE-2024-ISO2768 Date: [Current Date] Prepared by: Engineering Department Subject: Compliance and inspection criteria for machined and fabricated parts using ISO 2768-mk. These apply to external sizes, internal sizes, steps,

These apply to features (flatness, straightness, perpendicularity, symmetry, runout) .

Need to check a specific dimension? Use the tables above or refer to the official ISO 2768-1:1989 and ISO 2768-2:1989 standards.