Whilst essentially pressing records is an age old technology there
have been modifications to make it more efficient such as electronically
controlled presses. The basic principle is that we start with a
hydraulic press fitted with two pre-heated moulds and fitted with
stampers (which holds your music!).
The pre-heated vinyl matter is forced into the machine and sandwiched
between two completely dry labels and the stampers are copied exactly
into the vinyl matter. During this process the labels and vinyl matter
are pressed under a pressure of 100 or more tons at a temperature of
160°C (345°F).
After the pressing mould is sufficiently cooled, the press opens and
the vinyl record is removed, trimmed to the required size and visually
inspected.