The purpose of pencil scratch hardness tests is to determine the resistance of coating materials to scratch effects on surfaces.
the wolff- wilbon test, pencils of various degrees of hardness are
moved over the surface under a fixed pressure and angle to the surface.
The degree of hardness of the pencil which damages the surface is taken
as a measurement of scratch hardness e. g. “3H” hardness.
Instrument is supplied with set of hardness pencil, pencil sharpener, abrasive paper, operation manual, carrying case.