So I joined the hatch-a-long on backyardchickens.com on March 14th because my hens are getting old, laying fewer eggs and I've been thinking about replacing them. I put 38 eggs in the incubator, including 3 from a neighbor, closed it up, and let 'er rip.
I just couldn't get the temperature in the thing past 97/98 for the first 17 days. Should be around 100. On day 18 I "locked down" by adding water to increase the humidity from 45 to 62%, played with the thermometer once more and managed to get it to a nice steady 99.
I really had no expectation of anything hatching because I hadn't really seen the rooster successfully "do his thing" with any of the hens. However, if you don't try you don't know.
Chicks are supposed to hatch around day 21 depending on humidity and temperature. As of this morning, day 20, I hadn't seen any rocking, heard any cheeping, or seen the telltale pip where the beak first breaks through the egg. Then shortly after 10 am there was a loud cheeping and there was a chick, damp, completely out of its shell. I had to go to Alpena for the day and when I got back at 6 pm there were 9. Now at 10 pm there are 12, maybe 13, it's hard to tell, they're running around on top of each other and those little plastic windows aren't really that easy to see through. But I've got chicks! Pictures forthcoming.