I built my own incubator out of an old plastic/foam insulated igloo chest. 2 pieces of 8x10 glass for a double-pane viewing window on top. Have 3 bottles (1 qt each) of water for heat sink. And a piece of hardware cloth to float the eggs over the bottles. I'm trying to go "free" with stuff I have around my house (haven't spent a dime yet), and after about a week testing different wattage light bulbs and night lights, I decided to try Christmas lights. They are working the best so far and are easily pulled out to adjust temps. So, I'm wondering about constant "on" vs intermittent "on". I've been keeping the Christmas lights on 24/7 and the highest temp I've gotten was about 104. I'll add in some more vent holes, etc, but should I use the multi on/off timer thing that I have, or just keep it constant if the temps are good? Does it matter? All this testing is killing me!!!! I want to start some eggies, but hubby wont let me until we're back from our holiday trips (mid December) and he doesn't want to hire babysitters for chicks and can be home to turn the eggs, etc...... Guess he's right - I HATE THAT! Thanks!