Which end of the spoon gauge is used to inspect the minimum diameter of the driven head?

The NoGo end of the spoon gauge is specifically designed to ensure that the diameter of the driven head meets the minimum specification requirements. In the context of inspection tools, the NoGo end is used to verify that a part is not too small; if the NoGo gauge fits, it indicates that the part is out of specification and is therefore deemed unacceptable.

Using the NoGo end prevents parts with diameters that exceed the maximum tolerance from passing inspection, thereby maintaining quality control during the assembly process. This testing method is critical in aerospace assembly, where precise dimensions are vital for safety and functionality.

In contrast, the Go end of the gauge is intended for confirming that the part meets or exceeds the minimum size. The other options, Check and Measure, do not refer to recognized gauge ends and may add confusion when discussing the task of gauging size in engineering.