1. Height Gauge:
A height gauge is used for accurately centering workpieces in an independent chuck by measuring the height or position of the workpiece relative to a reference surface. It ensures that the workpiece is aligned properly.
2. Other Options:
Centre gauge (Option 1) is primarily used for setting tool angles, not for centering workpieces.
Dial indicator (Option 2) is typically used for measuring runout or eccentricity but not directly for centering.
Surface gauge (Option 4) is used for marking lines and measuring flatness, but it is not effective for centering a workpiece.
3. Why Height Gauge:
The height gauge allows for precise measurements of the workpiece's height and alignment, helping achieve accurate centering in the chuck.