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Tag: Rule #1

Rule #1 and Title Block Tolerances

by Crystal Bemis on March 3, 2025.

In this Question Line video, Jason answers a student's question regarding whether a default angular tolerance (found in the Title Block) must be taken into account in addition to the part meeting Rule #1 for it to pass inspection.

Flatness and Rule #1

by Crystal Bemis on February 10, 2025.

In this Question Line video, Jason explains how to calculate the flatness tolerance of a surface for a given example based on the size tolerances and Rule #1.

Rule #1 and Derived Median Line Straightness

by Crystal Bemis on May 30, 2023.

"Why doesn’t Rule #1 apply to the straightness of a Derived Median Line?" In this article, we look at both surface straightness and straightness of a feature of size to understand why Derived Median Line Straightness overrules Rule #1 of GD&T.

GD&T Rule #1: Envelope Principle

by Jason Richter on March 3, 2022.

Requires that a feature of size have perfect form at MMC. It's a default rule in ASME Y14.5 — one every engineer should understand before drawing a size dimension.

Circularity, Rule #1, and How to Report

by GD&T Basics on February 12, 2021.

This video is in response to a question that we received on our question line from Amber. Amber asked us if the tolerance value for circularity can be obtained by subtracting the upper limit of...