This is an incubator I built from a medical grade shipping container. Its very think styrofoam. I've been making small improvements since I built it last summer and yesterday I finally got my first 100% hatch! 12 eggs set and 12 chicks hatched!!
Here is a picture of my first hatch. You can see how thick the incubator is in this one! I used two panes of glass to better insulate it. I've also put the water sink (a bottle of water) behind a wire screen that also keeps the chicks off the fan, light bulb, and thermostat. I also switched out the wire on the bottom to a super fine hard ware cloth since I noticed the chicks feet slipping through it. There is also a much larger and flatter humidity tray under the wire. I use an egg carton with duck tape on the holes for the first hatch. It worked really great because I just filled it with water and chopped up sponge and the humidity did great! The best part, I could just throw it out when the hatch was done! No cleaning required! Speaking of cleaning, its pretty easy to clean. I usually just throw out the wire floor and replace it and then soak the water bottles in bleach water then rinse and let them air dry. Then I cover and tape over the lightbulb, thermostat, and fan, and fill it with a little soapy water and scrub it with a little stiff brush after I soak it for a bit! Rinse with the waterhose and let it air dry! The greatest part about this incubator is that it cost me only $17 to build!!