Problem with home made incubator

[ikoCRO]

English is not my language, so I will try to be as understandable as I can.
I made an incubator and I have several problems with hatching eggs.
I tested the first round of eggs at the recommended temperature of 37.8 C and my chickens hatch on 26 day?
On the recommendation of an experienced breeder, I raised the temperature to 40 C and my chickens hatch over a wide range of days from 21 to 27 days?
I assumed it was an incorrectly distributed temperature in the incubator, but I have a fan and that shouldn’t be a problem!
Bantam eggs are laid for 20 days, all without any problems,
-only eggs from large breeds of chickens are hatch incorrectly in days.
I also have a problem with the "bloody ring", more than half of my eggs have a bloody ring (only large breed eggs).

 

[jher77]

I tested the first round of eggs at the recommended temperature of 37.8 C and my chickens hatch on 26 day?

Temperature reading probably isn't right. Reading too high. Calibrate your thermometer.

On the recommendation of an experienced breeder, I raised the temperature to 40 C and my chickens hatch over a wide range of days from 21 to 27 days?

Yep. They also realized your temp is reading higher than what it really is. Calibrate your thermometer. Very important.

I also have a problem with the "bloody ring", more than half of my eggs have a bloody ring (only large breed eggs).

Again calibrate your thermometer and then see if that fixes that problem. You may still have one or two no matter what you do but half is unacceptable.

Bantam eggs are laid for 20 days, all without any problems,
-only eggs from large breeds of chickens are hatch incorrectly in days.

I don't know why bantam eggs would have a good hatch rate but regular eggs would not. When you work on your car, you fix what you know is wrong with it first. That often fixes other problems you don't know why. Calibrate your thermometer and go from there.

 

[Tonyroo]

Are these eggs from your flock or did you buy them and from who?

 

[ikoCRO]

Temperature reading probably isn't right. Reading too high. Calibrate your thermometer.


Yep. They also realized your temp is reading higher than what it really is. Calibrate your thermometer. Very important.


Again calibrate your thermometer and then see if that fixes that problem. You may still have one or two no matter what you do but half is unacceptable.


I don't know why bantam eggs would have a good hatch rate but regular eggs would not. When you work on your car, you fix what you know is wrong with it first. That often fixes other problems you don't know why. Calibrate your thermometer and go from there.

The first thing I did before starting the incubator was to calibrate the thermometer. I checked the temperature with a mercury,/digital thermometer (ordinary home thermometers) and finally with a digital thermometer / hydrometer.
I had big oscillations at + -3 C, which I fixed by putting cooling fan.
The eggs are from my flock of Wyandotte 4 + 1.

 

[dougieee]

Also, if this is a home made incubator does it have ventilation?
Where are you in the world? You havent mentioned humidity, if you are somewhere dry and arid you will need to add water as there will be very little humidity in the air.

 

[Tonyroo]

Well usually when some hatch late, it's cause there spot in the incubator is cooler and not at 99.5 but rather around 98 degrees. I find late hatches develop on the weak side. So they either die or become weak chicks.

 

[ikoCRO]

Also, if this is a home made incubator does it have ventilation?
Where are you in the world? You havent mentioned humidity, if you are somewhere dry and arid you will need to add water as there will be very little humidity in the air.

Yes, I made 4 holes on each side so that the air could flow. I live in Croatia, Mediterranean climate ... I think that humidity is the least problem, because my chickens hatch without any problems.
In the incubator I have 3 containers full of water occupying about 70% of the bottom surface.

 

[jher77]

How about some pics?

 

[ikoCRO]

How about some pics?

These are older pictures, in which there is a simple turner. In the last picture there is a metal turner which is now in the incubator.
This cheap white thermostat is just overheat protection, for temperature and humidity regulation, I use STC 2000.
At the top of the incubator is a spiral heater, which is placed around a plexiglass window.
Since it is obvious that the unevenly distributed temperature is the cause of the problem, I suspect the plexiglass window and the eggs underneath it?
Probably those eggs are colder than the eggs underneath the heater?
I’ve made incubators before and I have experience in that, I’ve never had problems like these.
Now I put 90 new eggs again, I turned off the fan, I covered that window, in about 20 days I will see the results.

 

[Davethebirdman]

English is not my language, so I will try to be as understandable as I can.
I made an incubator and I have several problems with hatching eggs.
I tested the first round of eggs at the recommended temperature of 37.8 C and my chickens hatch on 26 day?
On the recommendation of an experienced breeder, I raised the temperature to 40 C and my chickens hatch over a wide range of days from 21 to 27 days?
I assumed it was an incorrectly distributed temperature in the incubator, but I have a fan and that shouldn’t be a problem!
Bantam eggs are laid for 20 days, all without any problems,
-only eggs from large breeds of chickens are hatch incorrectly in days.
I also have a problem with the "bloody ring", more than half of my eggs have a bloody ring (only large breed eggs).

Why are you using your own incubator? Why don’t you have a normal professional one?
If your eggs survive at all, there is also the very high risk that the chicks that do make it to the hatching stage could be deformed, have curly toe or other defects and deficiencies. Since it sounds like you don’t have a clue what you are doing even with a regular factory made or commercial incubator, why bother??? Lol
The eggs wont mature properly and the ones that do will be few and possibly with problems. Are you wasting your time here???!