- buy a temperature controller, directly from manufacturer or for less from mcmaster-carr.
- this device runs on a logic controller programmed up to 60 C, and operates on a thermistor temperature probe, the resistance of which varies with temperature. add a constant 10 kOhm resistor in series with the thermistor in order to extend the operating range above 60 C.
- buy an electric heating element, such as a single cup water boiler or a crock pot, but one that uses less than 1.8 kW of power or draws less than 15 Amps of current at 120 V.
- calculate an instrument response function by measuring water temperature in an appropriate vessel such as a pot. here is one obtained by using a 8 quart pot with a 300 W heating coil.
- the linear fit in the temperature range of interest yields: Actual = 6.4 * Read - 57
- attempt to reproduce pierre gagnaire's egg cooked at 68 C (for 20 minutes) yields a most delicious entity with a delicate and uniform texture, neither "soft" nor "hard"
thanks to emil for the controller-resistor fix