Fog: Please explain fog machines

KimilyTheStrange · #1 (**permalink**) 08-15-2008, 12:05 PM

I love fog machines but have used them indoors and seen them in use in the states. We attempted to use a 400 watt in a cauldron, outside, last Halloween and the wind would just blow the fog away, quickly.
I live in Alaska with temps running from 30 F to 0 F degrees, with guaranteed wind, 5 mph to 30 mph.

Now what I need help with...

I don't understand the concept of fog chillers, especially with the outside temps probably being colder than the chiller is producing.
Please explain the idea of chillers, in laymen terms, heh.

And... can anyone suggest what we could use (I know the wind is a problem), and for inexpensive, that would produce fog in the cold conditions.

Thanks for any help and suggestions.

Skeleton Jay · #2 (**permalink**) 08-15-2008, 12:18 PM

Kimily,

For most of us, the temps don't dip that low. So, the fog chiller brings the fog down to temps below the outdoor temp. That allows the fog to stay on the ground for quite a while. Hot air rises .. cold air falls.

As for your wind problem. The only thing I can think of is a facade around your caldron to block most of the wind. You can setup some sort of themed walls around your prop. That may help a bit.

KimilyTheStrange · #3 (**permalink**) 08-15-2008, 12:23 PM

I'm tempted to get an old cloths drier and make steam instead... LOL.

TheReaper · #4 (**permalink**) 08-15-2008, 12:33 PM

Fog chillers make your fog desend to the ground. Good for a graveyard kind of scene

Frankie's Girl · #5 (**permalink**) 08-15-2008, 03:39 PM

Okay, the way the fog machine works is it heats up the solution and then expells it - the heat is necessary to make the solution "fog" along with the spray nozzle that breaks it into very fine droplets. Heat rises, therefore most regular fog machines will produce a heavy fog that goes pretty much straight up. Around most areas, adding ice/chiller lowers the temperature of the fog coming out to be cooler than the outside temp, which allows the fog to sink (cold air is heavier than hot) and lets you get the cool ground hugging fog effect.

Unfortunately with temps like what you're going to probably have, there would be no way to make the fog colder.

Fog's worst enemy is wind. The only thing you can do to try to keep your fog in your scene is to enclose it with a windbreak or just work the rising fog/wind into the scene - like a witch's cauldron or something.

KimilyTheStrange · #6 (**permalink**) 08-15-2008, 03:50 PM

Thanks Frankie's Girl for the explanation.

My conclusion... move to the lower 48!!

WickedBB70 · #7 (**permalink**) 08-15-2008, 08:01 PM

Hum..... I heard that for us "northerners", a haze machine would be best than a fog machine... What are your thoughts on this?

KimilyTheStrange · #8 (**permalink**) 08-15-2008, 08:04 PM

Hope thats nothing like getting Hazed. LOL.

Haven't heard of a haze machine... whats the concept? I'm assuming steam.

bradbaum · #9 (**permalink**) 08-15-2008, 08:34 PM

Haze machines produce a haze of fog that is thinner then what a fog machine produces and it hangs in the air for longer. Typically they are placed at the ceiling level to let the haze drift down from above. They are used a lot for laser shows as the haze shows the lazer beams real well.