The flatting process is the operation that consists in grinding the edge of drinking glasses to remove all the scratches and to finish the edge parallel to its base (foot). This operation is performed just after cutting, which generally produces an unacceptable edge quality, except for standard quality glass. Flatting has replaced the operation formerly carried out using silicon carbide abrasive belts 

The flatting disc has a diamond layer which is 20 to 40 mm wide and 0.5 to 1 mm thick, mounted on a thin backing ensuring the necessary flexibility when grinding.

 Two versions are available depending on the rim shape:

• the 1M2 wheel with complete flat rim,

• the 1Y2 wheel on which the diamond rim and backing present an angle to the outer edge (“entry tilt”).