To operate, attach riders to the scale arm at the numbered positions. The carriage is held down firmly by hand and moved in the opposite direction, to cause a trailing scratch. The large standard rider loads 100 g per division, while the small rider loads 25 g per division. This small rider may be used for making low-range measurements involving small increments of pressure, or it may serve as a vernier with the large rider in making more precise medium-range measurements.
The force necessary to cut through the film to the substrate.
The force required to scrape a path through the film, when the stylus begins its motion on an uncoated portion of the panel.