- The instrument consists of a base plate, panel holder with clamp, a series of mandrels and the handle/bending mechanism. The base should be secured to a suitable work surface, allowing the operator to turn the handle smoothly during a test. The diameter of the mandrel to be used depends upon the test specifications
- The instrument measures the diffusely reflected light from the test surface. The controlled conditions of illumination and angle of illumination allow surfaces to be characterised according to their lightness or darkness. A completely black surface will read a (zero), whilst a perfect white will be 100 units, recognised in colour measurement scale as the ‘Y’ value.