Make tools, fittings, and small metal pieces used in other products.
Measures inside and outside diameters of watch jewels and segregates jewels according to size: Gauges inside diameter of jewel hole by slipping jewel on graduated, tapered needle. Places jewel in precision jaw gauge and measures its outside diameter. Segregates jewels according to size and rejects those jewels failing to meet tolerances as fine as 0.0001 inch. May measure hole size of jewel bearings, using go-not-go gauge. May be designated according to measurements made as Jewel-Diameter Gauger; Jewel-Hole Gauger.