Go/No-Go Gauge vs Micrometer: Which to Use

A go/no-go gauge tells you whether a feature is within tolerance, as a pass or fail. A micrometer tells you the actual size as a number. They answer different questions.

When a go/no-go gauge is the better tool

For repeated checks on a production line, a fixed limit gauge is fast and gives the same decision for every operator, because it is set to the tolerance limits and does not need to be read.

When a measuring instrument is the better tool

When you need the actual size, for example to adjust a machine or record a trend, a micrometer or similar instrument gives the number that a limit gauge cannot.

Using both

Many shops use both: a measuring instrument to set up the process and a limit gauge to check parts during production. Accusize makes thread plug gauges, thread ring gauges, plain gauges and snap gauges, which are limit gauges, not measuring instruments.