Iso 20457 Tolerance Table Pdf May 2026

Let’s walk through a real-world example to solidify your understanding of the ISO 20457 tolerance table PDF.

Scenario: A company is designing a mounting bracket for an electric motor. The bracket is a sheet metal part (2mm thick, 200mm long). The motor has a shaft that aligns to a hole.

Result: The machinist reads the PDF, applies the correct deviations, and the bracket is cheap to produce (not over-toleranced) but still fits the motor. iso 20457 tolerance table pdf

Let us extract a typical row from the ISO 20457 tolerance table (PT2 – fine grade for a dimension not affected by parting lines).

Nominal size range: 100 mm to 200 mm PT2 tolerance: ±0.30 mm Let’s walk through a real-world example to solidify

Compare this to ISO 286 for metal (IT7 grade for 100–200 mm: about ±0.035 mm). The plastic tolerance is nearly 10x wider. This illustrates the core lesson of ISO 20457: Do not over-specify plastics.

The full table includes separate columns for: Result: The machinist reads the PDF, applies the

The tolerances vary depending on the material, as different plastics shrink and mold differently. The standard generally divides materials into groups: