Home made incubator -humidity issues- Advice??

[Minky]

My husband put together a home made incubator for me the other day.
It holds 36 eggs, and is holding temp nicely. However it was staying at about 35 % humidity no matter how many pans of water I put in it.
We figured it was because he insulated it with some RIDGID FOAM INSULATION board we had left over from our renovation. It is made to be breathable, since its for your house. So he sandwiched a layer of plastic between it and the plywood box. It has made a difference and can get up to 50% humidity.

HOWEVER I can't get it any higher, without turning off the fan. With the fan off, it goes to 75-80% no problem, but then the heat seems to also get a bit much, and when I looked last time it read 104 degrees.

He can set the fan to go on only when the light bulb (heat ) goes on.... but not sure if that will solve the problem.
Not sure how to set fan on only when it reaches , say 102 degrees? then off again at 99 degrees.

Any ideas....??

Also- I'm looking for a plastic bottom tray for the incubator. The part that the chicks will be hatching on, that will be above my water compartments.,. Dont want to use metal- need a plastic grid material. What have others used?
Thanks

A couple of photos.

 

[FortCluck]

You need to have a bigger pan. Adding small bowls of water isn’t going to change the humidity much.

You need the water to be even throughout the incubator like other factory made ones are.

 

[Ridgerunner]

The problem might be air exchange. You want some air exchange, especially later in incubation and at hatch. If they don't get enough fresh air carbon monoxide from their breathing can build up and they suffocate. But one time my lid did not set back right on my incubator. It held temperature fine but the humidity was a lot lower than it should have been. I finally noticed that the cord for the turner wasn't in its slot so there was a crack where the lid was supposed to seal. I don't now how much ventilation you have on that but you might want to try reducing it a bit and see what happens. Maybe a gasket of some kind around the lid or part of the lid to seal it better?

Humidity is controlled by wet surface area. Bigger pans, more pans, adding sponges or towels to wick water out can all create wet surface area for water to evaporate from.

To reduced surface area you can partially cover a pan, maybe with aluminum foil or some type of plastic. If you use a plastic bottom tray are you going to be covering some of that surface area and reducing the humidity? Not clear what you are trying to do.

I use 1/4" hardware cloth as a bottom for my incubator, it sets over the reservoirs. It gives good traction so their feet don't slip and does not impair air flow. Not sure what you have against metal? I'm not aware of any plastic mesh you can use but I've read about people using shelf liner. That's a solid surface.

 

[ChickenCanoe]

Humidity is a function of surface area, not volume.

 

[Minky]

I use 1/4" hardware cloth as a bottom for my incubator, it sets over the reservoirs. It gives good traction so their feet don't slip and does not impair air flow. Not sure what you have against metal? I'm not aware of any plastic mesh you can use but I've read about people using shelf liner. That's a solid surface.

Ok. I think we are good for air exchange. I have some tape that covers about 9 drilled holes. Pretty good fresh air when I need it, and a good seal when I dont.

Do you not find that the hardware cloth heats up and burns their little feet?

I was trying to replicate the little giants bottom which is like a hard plastic hardware cloth. Water pans underneath.

 

[Ridgerunner]

Do you not find that the hardware cloth heats up and burns their little feet?

Not at incubation temperatures.

 

[ChickenCanoe]

Ok. I think we are good for air exchange. I have some tape that covers about 9 drilled holes. Pretty good fresh air when I need it, and a good seal when I dont.

Do you not find that the hardware cloth heats up and burns their little feet?

I was trying to replicate the little giants bottom which is like a hard plastic hardware cloth. Water pans underneath.

Ages ago the bottom of the little giant was hardware cloth.
If 100F didn't burn the chicks' feet against the egg shell, the same temperature won't hurt them on hardware cloth.