During testing, technicians follow the ASTM D1630 abrasion standard guidelines.

First, the technician unlocks a bridge holding the gauges. The bridge is then lifted to allow the arms to swing backwards for mounting of the specimen. Each compound is then mounted and secured in the slots.

The operator lowers the arms to the metallic drums. The bridge is lowered and locked in place, with a calibration weight on every arm. The technician likewise calibrates the gauges, then sets the test’s number of revolutions. Finally, the operator presses the button to start the abrasion testing.

Prior to the actual testing, the equipment is given a break in run to allow the conditioning of the new abrasive paper. Garnet paper with #40 grit is used for the test. It can be used for 18 runs.

The abrader makes 500 revolutions employing break in compounds. It makes a second run of another 500 revolutions. Standard reference compounds are used for the second run. The compounds are discarded after the runs.

In the actual run, the new reference compound is used together with the previous three compounds. The four compounds then undergo four passes. Each pass tests three compounds.

The first pass if for testing the three previous reference compounds. The second pass is for the first two reference compounds along with the new compound. The third pass is for the third, together with the new compound as well as the first compound. The final pass is for testing the new compound, and the second and third reference compounds.

The operator runs the NBS tester until the compounds’ surface matches the drum’s shape. The gauges and revolution counter is set to zero. The operator then restarts the tester.

The tester runs until it 0.1 inch is scraped off from the compounds. The gauges indicate the amount of the material scraped off. The technician logs the readings and number of revolutions from each gauge. He then computes the number of revolutions required to abrade 0.1 inch from all compounds.

The tester needs another run, this time with new standard reference compounds. The reference compounds are then removed and a new compound is mounted on the arms.

The machine will stop from running when it has abraded 0.1 inch off the fresh set of specimens. The operator gets the values from the initial two runs in the latest computation.