Abstract: Methods of operating a thermal actuator, especially for use in a liquid drop emitter for ink jet printing, are disclosed. Methods are disclosed for operating a thermal actuator comprising a base element, a thermo-mechanical element extending from the base element, having a moveable portion residing in a first position and reliably operating at temperatures below a maximum temperature Tmax and including apparatus adapted to apply energy pulses to the thermo-mechanical element to cause a temperature increase therein and movement of the moveable portion to a second position. The methods for operating comprise determining a first energy pulse having a first energy, E1, and a first energy pulse time, t1, for suddenly increasing the temperature of the thermo-mechanical actuator, but not above Tmax.