What type of gauge is used to take measurements between the arbor and the parallel bar?

The thickness gauge is used to measure the distance between the arbor and the parallel bar accurately. This type of gauge is designed to check the thickness of materials or gaps with precision, making it ideal for situations where you need to ensure that components are properly aligned or that clearances are within specified tolerances.

Using a thickness gauge in this context ensures that the required spacing for equipment setup or part installation is maintained, contributing to the overall functionality and safety of the operation. This is especially important in precision machinery or setups where even slight deviations can lead to operational failures or inaccuracies in performance.

In contrast, the other types of gauges serve different purposes. A depth gauge is used for measuring the depth of holes or slots, while a micrometer is designed to measure small distances with great accuracy, usually in small increments. A dial indicator is typically employed to measure variations in surfaces or to check for runout or alignment, but it is not specifically suited for measuring the space between two parallel surfaces like an arbor and a bar.