A professional who tends battery of automatic machines that rough grind surfaces of lens blanks. Responsibilities include:

• Bolts block with mounted lens to rotating spindle of stone-roughing machine, and releases lever of feed mechanism that places lens block against revolving grindstone.
• Sets feed mechanism by adjusting setscrew controlling position of spindle.
• Removes lens block after specified period of time, and inspects lens for conformance to specifications.
• May turn valve to regulate flow of water over grindstone.