CIRCULAR GRAINING (PERLAGE)
Circular graining (perlage) is the process of creating round shapes with abrasive erasers on surfaces to be decorated. As a general rule, these shapes are applied in a circle of concentric shapes in relation to the centre or in relation to a hole.
Circular graining (perlage) is found mainly on the mainplates, under the bridges, or on the inner side of the case backs.
Circular graining (perlage) was regularly used in the days when the watertightness of the gearboxes was not as good as it is nowadays.
The circular graining (perlage) has the particularity of capturing dust and preventing it from falling into the gears and the escapement.
In high-end watches the parts of the plate and bridges around the gears are always circular-grained, as well as the inside of the case backs. This is in line with its technical utility at the time.
Circular grainging (perlage) can be done by hand with the help of a drilling machine.
The circular graining (perlage) can be done by hand or by machine.
To increase productivity, circular graining (perlage) is done by machine.