Dial Gauge

The dial gauge is a an indicating micrometer gauge that measures the penetration of the indenter under the applied load. The dial of the gauge can be rotated by rotating the outer ring of the face. Before starting the test, but after the ring S has been pushed upwards into the indenter housing by moving the sample table, the zero of the gauge scale is set to the pointer location. After loading the indenter (when the pointer moves to the dotted location shown in the diagram) , and then unloading the indenter, the new pointer location indicates the hardness of the sample.

The diagram shows the location of some B-scale readings. The pointer location indicates
that the sample has a hardness of Rockwell B-30.