Control furnaces that harden, anneal, or temper watch parts.
What does a Hardener do?
Controls furnace to harden, anneal, or temper watch parts: Presses button to admit gas mixture, forcing air out of furnace and burning mixture at entrance to prevent discoloration of parts and to maintain carbon content in parts. Places parts in metal basket or cylinder and inserts parts into furnace according to specified temperature. Advises on furnace temperatures and heat-treating time periods, and recommends procedures to produce desired hardness. Quenches pieces with air or oil. May cover parts with charcoal to prevent rapid heating causing discoloration of parts. May insert thermocouple into furnace and connect thermocouple to recorder.