Record press
From Wikipedia, the free encyclopedia
A record press is a machine for manufacturing vinyl records. It is essentially a hydraulic press with a closing force of 100 tons and is fitted with moulds. Labels and a vinyl pattie (pre-heated vinyl blob) are placed in the mould cavity while the moulds are being steam-heated. The moulds close and through the process of compression moulding the vinyl fills the cavity to take the form of the finished record.
Water is admitted to the moulds which both expels the steam and cools the moulds down. The press opens and the record is removed from the moulds. The overflow vinyl at the edges is trimmed and the records stacked and allowed to cool. Cycle time for a 7" record is about 15 seconds and for a 12" record about 25 seconds.
Stampers (metal plates, one for each of Side A and Side B) for each title to be pressed are fitted to the moulds. The stamper contains a negative image of the grooves.
Record presses were made by Alpha-Toolex (Sweden), Lened (USA), Hamilton Manufacturing Co, (USA), Southern Machine & Tool Company - SMT (USA), Taunus Ton Technik - TTT (Germany), Fabeldis (Belgium), EMI Records (UK) Philips (Europe) Miller (USA) and Finebilt (USA) together with two or three others. The last record presses ever made are said to be those built and supplied by Alpha Toolex to Melodiya Records (USSR) in the mid 80s.
