This is the second season using a cooler incubator. I made it like this one, but didn't cut the window in the top...

http://www.eyehit.com/degei/supportf.../inc/index.htm

I used only 1 ft of flexwatt and it just heats up to 89-90degrees full bore so there is little change that it will over heat if my thermostat fails. I have it set to 88.5. I used the same type fan and I really think it helps even out the heat. Also helps to bring it back up to temp after I have been checking out the eggs.

I had 100% hatch rate last year. And the first clutch from this year is cooking.....