Explain the difference between a gap gauge and a plug gauge. - Leaving Cert Engineering - Question k - 2017

A gap gauge is primarily used to determine the limits or tolerances of a round bar. It helps ensure that the diameter of the bar falls within specific measurements by checking the gap between the gauge and the bar.

In contrast, a plug gauge is utilized to test the dimensions of holes. It fits into a drilled hole to verify whether the hole meets the required size specifications. Essentially, while the gap gauge checks external dimensions, the plug gauge focuses on internal holes.