Incubators for hatching chickens come in several styles. Still-air incubators are heated by radiant heat that isn't circulated. Its effectiveness depends on correctly placing eggs and a thermometer in the incubator. Eggs must be turned four times a day in this type of incubator. A convection incubator includes venting holes to encourage heat distribution and airflow. You must keep this type of incubator humid with evaporation trays. A forced-air incubator uses a fan to circulate air and still requires evaporation trays. While all three options present advantages, the convection incubator is inexpensive and relatively simple in design.
Purchase an electric thermostat switch. Proper heating (within just several degrees) is essential to proper incubating, hatching and raising chicks.
Purchase or salvage a case appropriately sized for incubating your eggs. Wooden packing cases work well, as do beverage coolers.
Cut a lid for your incubator from lumber. Glue and nail it together, or use the lid that comes with the case, if you're using a cooler.
Line the inside of the case and lid with aluminum foil. This will reflect the heat in your incubator.
Place an aluminum pie dish at the bottom of the incubator. This serves as the evaporator tray.
Place two 1-inch by 2-inch pieces of wood on edge at the bottom of the incubator. Cut and place them to fit the shorter sides of the case.
Fit mesh wire to both pieces of wood, stretching it across the bottom of the incubator. Wrap the mesh or use nails to secure it to the wood.
Wire four tiny lightbulbs at each corner of the lid (on the underside). Do not use anything larger than 25 watts. Connect the bulbs to the thermostat per manufacturer's instructions. Place the thermostat in the center of the lid. Hinge the lid, if you're using a wooden lid.
Drill a 1/2-inch ventilation hole in each corner of the lid. Drill two 1/4-inch holes on each side of the incubator, just about 1 inch higher than where the eggs will sit. The incubator is ready to house eggs.