Glass Master Player

Optical Discs are made very much like the old vinyl records, except they are made from clear polycarbonate molded in an injection molding machine instead of a press.. 

The first step in making a "stamper", which is used in the injectiion molding machine,  is to make a glass master.

The glass master is created using the Laser Beam Recorder, and then stampers are made from the master.

It turns out that there is time and money to be saved if you can test the glass master and stamper before committing to the molding line.

This was a bit tricky, though, as the glass master is very heavy.

So the Glass Master Player uses a more powerful spindle motor to rotate the disc.

This Glass Master Player used a Marantz CD-72 player (heavily modified) to play a glass master, which is a 12" x 1" glass disc.  This requires a bigger motor, a heavy-duty loading mechanism, and numerous other modifications.