What specific are you using? (CNC machining, 3D printing, sheet metal fabrication?) What materials are your parts made of?
Part 1 defines four tolerance classes based on manufacturing capabilities: – Fine m – Medium c – Coarse v – Very Coarse
Ranges from ±0.1 mm (up to 10 mm length) to ±2.0 mm (up to 3000 mm length). Perpendicularity
When a drawing references "ISO 2768," it means that any dimension lacking a specific, localized tolerance must adhere to the generalized values defined by this standard. This drastically simplifies engineering blueprints, reduces drafting time, and streamlines quality control.
The most common standard for general mechanical engineering and machining. iso 2768 general tolerances pdf exclusive
These tolerances apply strictly to broken edges, rounded corners, and chamfers. Nominal Size Range (mm) Medium (m) Coarse (c) Very Coarse (v) Over 3 to 6 Over 6 3. Angular Dimensions
) directly next to that specific dimension. The general "mK" rule will handle the rest of the part. Creating an Exclusive Internal Reference Document
The standard dictates that larger nominal dimensions are allowed larger deviations. Below is the data typically compiled into a reference PDF for linear dimensions (values in millimeters): Permissible Deviations for Nominal Size Range (mm) Over 3 to 6 Over 6 to 30 Over 30 to 120 Over 120 to 400 Over 400 to 1000 Over 1000 to 2000 ±0.05plus or minus 0.05 ±0.05plus or minus 0.05 ±0.1plus or minus 0.1 ±0.15plus or minus 0.15 ±0.2plus or minus 0.2 ±0.3plus or minus 0.3 ±0.5plus or minus 0.5 m (Medium) ±0.1plus or minus 0.1 ±0.1plus or minus 0.1 ±0.2plus or minus 0.2 ±0.3plus or minus 0.3 ±0.5plus or minus 0.5 ±0.8plus or minus 0.8 ±1.2plus or minus 1.2 c (Coarse) ±0.2plus or minus 0.2 ±0.3plus or minus 0.3 ±0.5plus or minus 0.5 ±0.8plus or minus 0.8 ±1.2plus or minus 1.2 ±2.0plus or minus 2.0 ±3.0plus or minus 3.0 v (Very Coarse) ±0.5plus or minus 0.5 ±1.0plus or minus 1.0 ±1.5plus or minus 1.5 ±2.5plus or minus 2.5 ±4.0plus or minus 4.0 ±6.0plus or minus 6.0 Angular Dimensions Reference Table
While we cannot host copyrighted PDFs directly due to intellectual property laws, this article serves as your complete technical reference. For a legally blank, editable template drawing note, refer to the "Exclusive Annex" at the end of this article. What specific are you using
In precision manufacturing, specifying individual tolerances for every single dimension on a technical drawing is inefficient. It clutters blueprints, increases design time, and drives up production costs.
It indicates tolerances for linear/angular dimensions and Class K tolerances for geometric features. Example 2: ISO 2768-fH
ISO 2768 is an international standard intended to simplify drawing indications. It applies to parts that are manufactured by metal removal (machining), sheet metal forming, or casting, where the general tolerances are sufficient without individual inspection.
ISO 2768-2 specifies general geometrical tolerances for features that do not have individual tolerance indications. It mainly applies to features produced by the removal of material, such as in turning, milling, and drilling. This part defines three tolerance classes: , K , and L , where H is the tightest and L is the coarsest. Perpendicularity When a drawing references "ISO 2768," it
ISO 2768 is an international standard that defines general tolerances for linear and angular dimensions, as well as geometrical features like straightness and flatness. Its main goal is to simplify drawings by providing a standard baseline for "good workmanship". The standard is split into two critical parts: ISO 2768-1
ISO 2768 is an international standard that defines general tolerances for linear and angular dimensions without individual tolerance indications. It applies to parts that are produced by metal removal or formed from sheet metal.
| Nominal Size Range | f (Fine) | m (Medium) | c (Coarse) | v (Very Coarse) | | :--- | :--- | :--- | :--- | :--- | | 0.5 up to 3 | ±0.05 | ±0.1 | ±0.2 | — | | >3 up to 6 | ±0.05 | ±0.1 | ±0.3 | ±0.5 | | >6 up to 30 | ±0.1 | ±0.2 | ±0.5 | ±1.0 | | >30 up to 120 | ±0.15 | ±0.3 | ±0.8 | ±1.5 | | >120 up to 400 | ±0.2 | ±0.5 | ±1.2 | ±2.5 | | >400 up to 1000 | ±0.3 | ±0.8 | ±2.0 | ±4.0 | | >1000 up to 2000 | ±0.5 | ±1.2 | ±3.0 | ±6.0 | | >2000 up to 3000 | — | ±2.0 | ±4.0 | ±8.0 |
Geometrical tolerances for features (such as flatness, straightness, symmetry, and run-out).