Getting the eggs to ambient
Your eggs need to settle for a minimum of 12 hours before incubation. Eggs should always be stored with the pointy end down prior to incubation.
Setting the temperature
Once you have your incubator plugged in the first job is to set the temperature.
The most difficult part of this is to make sure you have an accurate thermometer. This is critical in calibrating the incubator and setting a suitable temperature, a few degrees out and you will encounter problems.
After the first hatch, you can raise or lower the temperature by what the hatch tells you. If they hatched early the temperature needs to be lowered. If they hatch late the temperature needs to be raised.
It is much more damaging to have your incubator set higher rather than colder. Although it is not recommended, slightly lower temperatures will not kill the chick embryos, but can increase incubation times and possibly produce weakened chicks.
Having the incubator too high will result in no eggs hatching at all.
The first job is to turn the dial on the thermostat fully clockwise to let the thermostat heat up to your approx target temperature 100 F.
Examining the thermostat in the incubator once this approximate temperature is achieved then turn dial back until the bulb switches off. You are now at the approximate incubation temperature. Its a good idea now to make small changes to the dial to fine tune and get your ideal temperature. The homemade still-air incubator (no fan): should be around 38.5 degrees measured at the TOP of the eggs.
Adding the eggs to the Incubator
By the time you have got your eggs ready for setting your incubator should have been running at least 24 hours. This gives you time to learn what’s going to happen in your incubator and allows you to make any necessary adjustments before setting your eggs.
A definite way to ruin hatching eggs is to put them in the incubator without having it properly adjusted. If the eggs reach an internal temperature of 105 degrees you can kiss them good-bye. Take note that I said “internal” temperature. Don’t confuse internal egg temperature with internal incubator temperature. The temperature in an incubator changes constantly, rising and lowering. The temperature inside the egg will be an average of this temperature swing in your incubator.
Humidity
The ideal humidity in the incubator for the first 18 days is 55 - 60%. You can add a small tub of water if required if you are struggling to achieve this level. In the last three days before hatching some people recommend increasing the humidity levels up to 70% by adding more surface water. You can sneak by with humidity numbers that aren’t very accurate, but the combination of poor humidity and temperature will definitely cause problems at hatch time.
If your temperature is not accurate you will DEFINITELY have problems at hatch time. The bigger the deviation from the proper temperature, the bigger your problems will be.
As seasons change, so does humidity. When you are incubating eggs in January and February it will be very difficult to maintain a humidity that is as high as you like. That’s because the outside humidity is so low. By the same token, when you are incubating in June and July the outside humidity is usually much greater and the humidity in your incubator will most likely get much higher.
Hatching problems will change as the season progresses. If you are doing things the same way in July as you were in January, you have to expect different results. All I am trying to say here is that your incubator humidity changes directly according to the outside humidity. Low outside, low in the incubator. High outside, high in the incubator. To adjust for these problems, you need to change the surface area of water in your incubator.
We also have to remember that our incubator needs to keep the eggs at an average temperature. It will swing below and above the target temperature a degree either way as the bulb switches off and switches back on.
Turning the Eggs
Turning them is critical. A good tip is to turn your eggs an odd number of times each day. This is important so you don’t leave the eggs laying on the same side each night which is the longest period of time they go each day without turning. Draw a small pencil line on one side of each egg. Then when you turn them, it will be easy to see that you switched them from one side to the other. Most eggs will be turned on their sides. Try to set the eggs so that the large end of the egg with the air sac is higher than the small end.
Troubleshooting
The incubator is simple and works well but please be aware of the following.
- If the thermistor sensor in the incubator is touching the eggs your thermostat will be effected and the temperature will alter.
- An accurate thermostat is essential, if in doubt use two.
- A good tip is to use a hygrometer to know the humidity in the air. Adding a reservoir full of water when the air humidity is already 70% won’t be useful to your hatch.
- A thermostat touching eggs will also produce inaccurate readings.