Job Description:

• 1) Operates bench lathes to drill holes of specified size in jewel bearings: Sharpens diamond drill, using diamond cutter and other tools.

• 2) Mounts chuck in lathe and inserts shaped and ground sapphire bearing between jaws of chuck, using tweezers.

• 3) Starts lathe and holds drill against center of bearing, cutting halfway through.

• 4) Reverses bearing in chuck and drills through center of bearing from other side until holes meet.