If the chick is taking over 24 hrs to hatch something might be wrong. It could be stuck. Sometimes they can take 24 hrs or more from pip to hatch. I let them go at least 24 hrs then if I need to I will carefully pick off the shell around the area the chick would normally zip without tearing the membrane and with a Q-tip or my finger I moisten the membrane where I picked off the shell then wrap the egg in a warm moist towel and put it back into the incubator. After a while if the chick doesn't hatch then I help it. If I see any blood I stop and immediately but the egg back into the incubator for a while longer. Then if the egg doesn't hatch I help it out. Sometimes they die but sometimes many live. I had a hatch last weekend where one chick had pipped so I zipped it but after another day in the hatcher it still hadn't hatched. It had shrunk wrapped. It's poor little feet were all curled. I finally hatched it and cleaned it up and put it in one of the hatchers as the other chicks were picking on it. I did hand feed it for several days. Its little feet did uncurl by but it still had spraddle legs. I think that is why it didn't hatch in the first place as in the beginning it couldn't walk. It is now normal in every way except is is smaller than the rest of the chicks but it is eating, drinking, sleeping and pooping.