Stampers for record pressing are manufactured from such mastered
lacquers by a three-step electroforming process in electrolytic baths.
It is recommended to start these processes with already cut lacquers as
soon as possible to avoid deformations of grooves caused by heat and
other environmental factors.
During the galvanic process a metallic copy of the lacquer foil is
made. For this step the surface of the foil has to be made electrically
conductive. Then a thin silver layer is applied, this silvered foil is
immersed in a galvano-plastic nickel bath and the foil works as the
cathode and the nickel is used as anode. Once electricity flows through
the solution, the metallic nickel settles on the silvered surface of the
foil. After achieving the desired thickness (ca. 0,23 mm), you have to
remove the foil from the nickel layer.
By doing this you receive the first Galvanic, also called “father”.
It is a negative, which means, instead of grooves there are the
corresponding elevations. At this point the “father” is used for making
another copy, called “mother”- this one is then used for making the
“son”, which is the stamper that is essentially used for pressing. The
stamper is then attached to the press and used to press the grooves into
the vinyl.
Pressing vinyl records over and over again is hard on metal stampers,
causing them to wear out over the course of a pressing. A set of
stampers is usually good for around 1000 to 1500 pressings. As long as
they are kept in good condition, you can make virtually endless stampers
from a single mother. Once a stamper has been used it will be recycled.
