Your music is converted to analogue signals which vibrate a diamond cutting stylus. the lathe cuts a groove (left right- stereo) ( up and down -bass and treble) into a 14" aluminium disk covered with a plastic coating. (the Lacquer) . THE ENGINEER adjusts the EQ and compression to get good grooves.
The lacquer is sprayed with a silver solution (to make it into a good conductor of electricty) it is then placed into a bath containing a nickel suphamate solution, an electric current is passed though this and small nickel particles are attracted to the surface of the lacquer . this is the (+ positive) this goes into another tank and the process is repeated to produce the mirror image the (-negative) these are keep as masters. a further copy is made ( stampers) these thin metal plates are then fitted to a record press
A puck of vinyl material is squashed between two heated moulds under hydraulic pressure, the press puts the labels on at the same time. the 12" is then trimmed, cooled and packed !!!! this is the much shortened version of how vinyl is made . !!
http://www.youtube.com/watch?v=xUGRRUecBik