Weighing eggs for humidity control?

[Ispahan]

So, I have been reading a lot of books and manuals about the best ways to artificially incubate eggs. Many of them, including the manufacturer of my incubator (Brinsea), state that the best way to control humidity during incubation is to weigh the eggs periodically to ensure that they achieve an ultimate 13% weight reduction (for chicken eggs). Humidity can either be raised or lowered throughout the incubation process to ensure this 13% weight loss by day 18.

My question is: how many of you weigh your eggs to control incubator humidity? Do you use an "egg weight loss graph" for your eggs?

And, finally, is this whole process easier said than done?

Thanks,
Corey

 

[Paganbird]

I have never weighed eggs for humidity. Actually, I have never weighed "hatching eggs" at all.
I weigh my table eggs that I sell locally to determine which are large or extra large.
I just keep my humidity where it works for me and leave the rest up to the chicks.

 

[BirdBrain]

I weighed my eggs this time at start, 7,14, and 18 days to track their loss. I have some that made it into the range and most did not when I kept my humidity between 30-40. Usually it was low 30's. I did not adjust my humidity as I am waiting to see how the hatch fairs. I used an excell spread sheet to do my calculations.

 

[Gypsy07]

Before I tried my first hatch, I had read about weighing to check humidity. I didn't have a hygrometer when I set the eggs so I weighed them instead. I set 11 eggs but I only weighed three, on a digital scale that measures to the nearest gram. I wrote their weight on the shell in pencil and each time I candled them, I also weighed them. I didn't think it was difficult or complicated at all. I got a hygrometer 12 days into the incubation, but I still weighed my eggs right before lockdown to check they were progressing as they should be. I found it very reassuring, as I thought the air cells in my eggs were far too big compared with diagrams in my chicken book. But when I weighed them before lockdown I found that they were all down by 12-14% which was just about right.

I didn't use a graph or write anything down, I just used a calculator to figure out what weight the eggs should end up at.

Eg: 64g to start with... Should lose 12.5% of that... Leaving 87.5%... So 64g x 0.875 = 56g

I wasn't obsessive about it, or too worried about getting it exact. But I did find it helpful.

 

[Katy]

I don't weigh mine. I just keep an eye on the air cell and whether it is increasing in size like it should be.