A dial indicator touching the face of a shoulder on a shaft provides information about what?

A dial indicator touching the face of a shoulder on a shaft is primarily used to measure shaft end float. When the indicator is placed in contact with the shoulder, it can detect any axial movement of the shaft as it is pushed or pulled along its length. This measurement reveals how much the shaft can move in the axial direction, which is critical for ensuring proper alignment and function within a mechanical assembly.

While the dial indicator can also be employed to measure runout and bearing fits in different contexts, in this specific setup, it is designed to provide data on end float specifically. Understanding the end float is essential for ensuring that there is no excessive movement that could lead to misalignment, wear, or failure of the components involved.