Part 2 of this little backgrounder looks into the process of pressing records.
In the previous part, I explained the creation of a master record by cutting the analog sound into grooves on a lacquer or various plastics plate.
This freshly cut record can now be played on a record player. Or it can be used to create the basis for the mass production of records.
In order to create a great number of records, the master record has to be cut into lacquer. It will be thoroughly inspected with a microscope. If it is acceptable it will be covered with a fine layer of silver, followed by a variety of harder metals. This is done by electrolysis.
If this process is ready, the lacquer (black) will be broken of the metal (red).
This “metal” is called the “master” and it has ridges where the grooves were on the lacquer. This “master” is still to delicate to put it into a brute force records press. So a number of “mothers” will be created – again with an electrolysis process. The mother has “grooves” and it can be played. But it is used to create “stampers”. This process has to be done for the “A” and “B” side of the record.
The stampers will now be mounted in a record press. The press will be heated (usually with steam) and a small clump of vinyl (a “cake”) is inserted. The press now clamps down and the grooves will be pressed into the vinyl by a force of up to 150 tons.
That’s about it. A new vinyl record is born.
In short: The process is as follows:
Cutting – Preparing – Pressing.
While the cutting can be done in audio studios, the preparation and cutting is a complex process that requires an industrial environment.