When I first made my Miss Prissy chic bator I tried the thermostat but could never get it to even relatively stabalized temps. So I switched to a dimmer and that was great for 2 hatches. Now it's amazingly hot here in Florida and even with the a/c going full blast the ambient air temp fluctuates during the day. I left yesterday morning with one thermometer reading 98 and one of them 99. I left the dimmer exactly where it was. When I got home yesterday late afternoon the bator temp was 111 degrees. Yep, I probably lost that set of eggs. It was the ambient room temp that was up 3-4 degrees. So last night I took the dimmer off and reinstalled the thermostat. While installing it the light bulb in my brain came on...No wonder the thermostat didn't work well the first time. I had bolted it right up to the inside wall of the bator and the hole in the back which senses the air temp couldn't do it's job. It had to wait until the bator wall was at the set temp. So I loosened the thermostat and placed a small springy piece of metal behind it and then tightened the nuts up. Now the thermostat is about 1/2 away from the wall and the temps don't swing more than 4 degrees. No more getting up all times of the night to check the bator temp. Hopefully this will help someone who is having temp swing issues in their homemade bator.