I read someplace here to do that. I think it had to to with the air sack. Sorry I don't really remember. Also, I like them in the crate......it has lots of open areas for circulation of air.....because the chicks that hatch don't kick the other eggs around.
I may have to cut holes in the bottom of some egg cartons and try that. Last time it drove me nuts that the new babies were knocking the other eggs around everywhere. Made me nervous! And I had 2 die in the eggs after some had hatched and always wondered if that was y. They were not shrink wrapped or anything, and had already pipped. So, I'll have to figure out something like that!!