Does the size of the incubator matter...?

[as110]

... when I want to increase the humidity and it will not rise or stay up?

When I tested the home made incubator, I was able to have 30-40% without water, and 70-75% when I added water in the tray in the bottom of the box. Now that we are in lockdown, I have added a tea pot worth of warm water (tried almost boiling steaming too), in the last 3 days, 3 times. The temperature is steady, and the humidity will not rise above 60%. I am lucky if it makes it that far. At the moment it is 56% and the first egg pipped. I feel like I am going to lose my mind over this, I don't know what to do at this late stage of the game. This is the third hatch, first one was a flip due to power outage and heat spike, uninsulated box. Second time 2 eggs hatched, and all the others had different issues when I opened them. The box was insulated plastic. I know the temp and humidity were just right. This is the third time, the only thing I changed from last time was I moved the fan from the center top of the box to the side because it was hanging in too much and it interfered when I tried to reach the eggs in the far end. I have a small side door to reach in, I don't open the entire top, so when my arm is in the box, it pretty much covers the entrance and very little heat or humidity is lost. It is much better than opening the whole top.

Would a smaller or shorter box be easier to maintain? Did I make a mistake with moving the fan to the side from the center?

We are on day 20, with 2 internal pips and one external pip. 8 eggs total in the incubator. RH at the moment is 56%. Temp is 99.5-100F. Air cells are perfect size.
:0[

 

[Tabasco Jack]

It's not so much the size of the incubator that affects the humidity. It's the surface area of the water container. If your water container is a large as can be area wise, you can try adding some sponges that will stand up.
And I wouldn't add water any warmer than 100 degrees. You'll spike the temperature inside.
As for the fan, I think it's better to have a fan that causes the air to circulate rather than one that blows on the eggs.
It's too late to add any sponges now, but after this hatch is complete do a trial run and experiment with container size and sponges. You may need to cover part of the container with foil to lower the humidity during the first 18 days and then remove the foil and add sponges to raise it.

 

[as110]

The pan is the same size as the entire bottom of the box. The first 18 days are ok on the humidity without adding any water. With a dry tray it is 30-40%.
My husband made an emergency humidifier now. He thinks the eggs are taking in the humidity because the previous hatching had a perfect RH. The house was warmer too when the furnace was going. I will be up all night to monitor humidity and temp. I hope the other ones will start pipping tonight too.
Humidity is now 70-80%. It falls back down if I stop the humidifier. It is very crude but gets the humidity up very quickly where it needs to be. This is not the time to experiment with different settings, we just have to get through the next 24 hours until they all hatch (or whoever is ready to hatch), so I will have to keep it the way it is now.
I think I will make a smaller box after this batch so I won't have to humidify so much air space on top of the eggs.

When the fan was in the top center, it was blowing horizontally, and now it is blowing from the side horizontally onto the other side. Basically where the fan is what's changed, it is still blowing sideways, never down onto the eggs.

How much ventilation do I need when the box is large in relation to the number of eggs inside? The inside insulation is plastic and waterproof, the top is taped with a plastic tape and any gap I found I taped with plastic. There is only the gap around the light bulb and a few inches on the corners where fresh air would get in, and humidity can escape, so it isn't airtight. I can't believe that little space can mean so much loss of humidity if that is the case. ??
Should I seal the entire box to prevent humidity escape?

 

[Granny Hatchet]

maybe why your losing them. they need ventilation. Once they do the internal pip and breathing oxygen then need fresh air coming in or they will suffocate. 60 isnt bad humidity as soon as one chick hatches it will raise the humidity higher. Member Sally Sunshine has some great articles on all this.

 

[as110]

maybe why your losing them. they need ventilation. Once they do the internal pip and breathing oxygen then need fresh air coming in or they will suffocate. 60 isnt bad humidity as soon as one chick hatches it will raise the humidity higher. Member Sally Sunshine has some great articles on all this.

OK then, I won't seal the box. There is a good hole where the humidity goes in and fresh air is also going in there.

There are 2 more eggs rocking. The first one looks like it has been in the same stage since 4PM. but it is chirping and moving from time to time. I can't see if it is zipping on the bottom or if it is stuck in that first pip.

 

[Tabasco Jack]

Agreed, don't seal the box. I think the openings you have are probably good. Although, before lockdown I would open the box every 2-3 days for a couple of minutes and let in lots of fresh air.
Here in north Georgia the relative humidity inside the house varies from 40 - 60% and I incubate at 35 - 40% and then increase it to 55 - 65% for lockdown. When they start hatching the humidity and heat increase from their activity. Personally, I think 70 - 80% is too high. But, if it works for you then go for it.

 

[Ridgerunner]

You've ben getting good advice. The chicks need fresh air later in the incubation cycle, so keep some ventilation going. Depth of water in the reservoir doesn't control humidity, surface area that water can evaporate from does. So adding sponges or cloth that can wick water out of the reservoir to increase surface area will raise humidity.

In my Hovabator, I can get quite a swing in humidity inside based on the air going in, temperature and humidity of that air makes a difference. I've noticed a ten percent difference in my current incubation, based on temperature and humidity of the air going in.

You'll get different opinions on what is the best humidity for incubation and lockdown. Different things seem to work for different ones of us, maybe because of the different conditions we hatch in. I try to get my humidity up to 65% during lockdown but when chicks stat hatching and adding moisture to the inside it can get up as high as 85%. I'm OK with that.