I've given up hope!! GRAPHIC PICS

[crossedwires]

ok...........this is what i would do with your setup.
to me it looks like you have the bulb stood upright personaly i would mount it on the side wall on its side (if you see what i mean) make sure there is a large enought gap so it dosnt melt the polybox. also move the light to one end not the middle, now i know this dosnt sound logical but the reason to do this is dissipation, if you have the bulb at one end you have a lower hot spot area and the heat dissipates quicker.

2. move the fan closer to the bulb so it dissipates the heat quickerfrom the bulb.
3 use a double layer of wire (one on top the other) this acts as a heat sink and goes a little way to stop the top layer conducting all the heat and passing it to the shells.
4 4 my personal fave add a fan speed controller

 

[BrownEggFan]

Jars, thanks!

I don't plan to purchase any shipped eggs in the near future. I've read here on BYC that they usually have very low hatch rates and can be quite expensive. I just want to hatch some chicks, have my 4 year old daughter participate and get a few replacement birds. I have 6 hens right now and that has been an ideal number.

Crossed, thanks for the input. The bulb is on its side (not upright) and is located on the far right side of the bator. It is covered by a piece of sheet aluminum to act as a heat shield; I may try mounting the fan closer as you have suggested. Also, I have a piece of sheet aluminum covering the bottom of the bator to protect it from the heat of the bulb as well as to act as a heat sink (in addition to the jar of water).

 

[crossedwires]

i couldnt see the bulb from the pic so i assume it was under the wood in the centre, idealy you want a fan near the bulb under the heat sink as well so in effect its cooling the glass on the bulb what this does is take the heat away from the bulb quicker and makes a more even distribution of the warm air, but keep a fan in the main part of the bator as well. if your using something like a old pc power supply to power the fan in the pic then try running the fan on the 5v line from the power supply, i dont like to normaly control fan speed with voltage drops but in this instance if the fan runs ok at 5v then you will still get a decent amount of air movement but you also cut down on egg evaporation wich can be a problem in the smaller type bator's with a pc fan in.

 

[BrownEggFan]

Crossed, the item below the block of wood is the lid of the p-nut butter jar. I'm using an old 3.7v transformer that I found in a box of stuff in the basement. I think it was a charging cord from an old cell phone. The fan runs fine and seems to push enough air to circulate it without so much as to create a "draft" and cause undue drying of the eggs.

 

[crossedwires]

if its a pc fan then its rated at 12v so if its turning ok on 3.7v i would say thats perfect for the size area you have

i would still add a fan near the bulb blowing onto the glass.

a peanut butter jar!!! its no good i will have to go and get knew glasses

theese old eyes aint what they once were