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Fun with Fog Generators
BoomZilla writes "Only
10 or so shopping days to Halloween. If you're at a loss for a project
this weekend check out gotfog.com for
a full set of detailed instructions on the construction of a Fog
chiller. "What's a fog chiller?" you may ask. And rightly so.
Let me explain. A fog machine dumps fog juice on a heating plate to
produce oodles of the white, floaty stuff. Problem is that it doesn't
hug the ground like you see in the movies. An alternative that is employed
to create the ground-hugging variety of fog is a dry ice machine (which
heats up dry ice and disperses the resultant cloud of fog). The problem is
that dry ice is (a) expensive and (b) not always that easy to get. Enter
the fog chiller. The chiller can be built very inexpensively (major cost
is the sacrifice of a largish cooler) and works with a regular fog machine
that consumes low-cost fog juice. Go on, give it a try. You know you want
to. And just imagine the look on the faces of your little ghouls and
ghosts come the 31st when your house looks like boot hill on steroids."
(c) could get you put on a list of suspected pot growers faster than a subscription to High Times.
Why is Triangle Man so MEAN?
In only a few hours, I will be helping in the construction of one of these! We already have all of the materials.
:)
Glow sticks and some tin foil reflectors make for good glowing green fog, by the way.
My friend bought a fog machine for his dorm room last year, and because he thought his fire alarm was heat and not particle detecting, he filled his room with fog. Turns out, it was a particle detector after all, the fire alarm went off, school security came and made fun of him mercilessly for intentionally filling a room with smoke... then they wrote him up. It was funny...
Once upon a time...
And just imagine the look on the faces of your little ghouls and ghosts come the 31st when your house looks like boot hill on steroids.
:)
Or you could just use mustard gas instead of some silly fog, that'll teach the little buggers right enough and betcha they wont come around bothering you the next year anymore.
The problem with dry ice is there are organised networks that specialise in stealing it. I've tried to dry ice several times (by leaving it out in the sun) and when I got back it was all gone.
RMN
~~~
And gosh, come to think of it, who'd ever have thought that smoke coming out of your case was an indication of a successful mod?
A couple years ago I was working at Guitar Center and our store manager had just been promoted to regional manager so we had a new manager coming in. They went out to lunch to go over some store specifics and one of them employees decided to break out the fog machine and fill up the new managers office. They came back from lunch everyone said their goodbyes and he left. The new manager introduced himself to everyone then went into the back to check out his office. Bye now the room was absolutely packed with "strawberry" fog, he opened the door, walked in, and sat down like nothing was wrong. :)
sig.
OOh, finally, something on Slashdot that I can comment authoritatively on! (I'm a stagehand, and often use atmospheric effects)
I would just like to refute the posters assertations about dry ice foggers. Firstly, dry ice is certainly NOT expensive. Prices usually fall in the $0.50 to $1.00 / lb range, depending on the form (block, pellets, etc.) and supplier. Which brings me to the second point, availability - Go to your local grocery store. If they don't have it (most in southern and western states usually will), they'll be able to tell you who will.
Once you have the dry ice (I'd suggest about 25-35 lbs. for a good, long show), it's very easy to turn it into fog. Step 1 - pour hot water over it. Step 2 - there is no step 2! There are many many pre-made machines for this purpose, such as the City Theatrical Aquafogger, which are available for rental, but it's such a simple device, anyone here should easily be able to make one on their own.
The basic things you need are as follows - a barrel - big enough to hold the dry ice, plus all the hot water that will be poured through it. A basket, to hold the dry ice in, above the level of the water. A fan and a tube, to take the resultant fog, and put it where you want it (dryer hose works very well for this). And finally, a method for pouring large amounts of very hot water over the dry ice - the faster the rate of pour, the faster the sublimation of the dry ice, and hence, the larger the volume of fog generated. For the water-pouring, something as simple as a 5-gallon pail is quite sufficient.
One down side to a dry-ice fogger, however - that 25lb load will only last about 10 minutes, and the fog only a few minutes longer than that. If the effect that you're looking for is a long-lasting, room-filling, hanging haze, then you'll be better off with an oil-based fogger. (Just avoid prolonged breathing of concentrated amounts of the fog - it's been shown to produce many respiratory ailments - and that was the professional stuff)
If all the world's a stage, anyone who says they want better lighting spends far too much time in a dark theatre.
The problem with dry ice is that it's dangerous (CO2 asphyxiation) in closed areas, and outdoors nothing will work terribly well.
I've put up a mirror of the special projects page at gotfog.com, as well as the "making fog hug the ground" and "vortex" special projects. The mirror should be significantly faster than the original, and can be found at http://www.msu.edu/~brownd41/mirror/gotfog/index.h tml
Dry ice shouldn't be too expensive if you get it from your local industrial chemical supply store (A place that sekks propane, helium, dry ice, etc) . Dry ice is probably more expensive from a party outlet.
Last halloween I bought several pounds of dry ice from a local industrial chemical supply store for about $15 total. I placed the dry ice in a cheap black 5 gallon "witches cauldron", which I got from the local Haloween store.
To create the fog, I simply placed the ice in the cauldron, and periodically added warm water when I saw trick-or-treaters. The warm water melts the ice, and you get fog.
The dry-ice provided enough fog rolling down my front steps to freak out the neighborhood kids. This fog lasted approximately 4 hours.
For added effect, I placed a couple of those green and red glow sticks inside the cauldron (Since glow sticks glow less when cold, I placed the sticks on a pedestal above the cold ice and water), replaced my porch light with a black light, and added a bunch of those green-spiderwebs from the halloween store.
This gave the whole porch a nice eerie glow, especially with the green-glow eminating from the cauldron.
Whole cost of this operation, including dry ice $15 for several pounds), cauldron ($5 at halloween store), black light ($2 at hardware store), glow sticks ($2 each) and spiderwebs ($3 a pack) was probably $25. I'm going to do the same thing this year.
"Can of worms? The can is open... the worms are everywhere."
Plenty of it around. It certainly makes oodles of thick, ground-hugging fog, especially on a humid or drizzling day. Careful not to "burn" yourself with it, though.
My father used to (jokingly) complain about neighborhood kids on our lawn. (There never were, which was part of the joke.) Then he would confide that he knew the perfect way to keep them off the lawn.
Land mines.
"Tough on that first kid, but they learn quickly," he'd add.
You cannot apply a technological solution to a sociological problem. (Edwards' Law)
In only a few hours, I will be helping in the construction of one of these! We already have all of the materials.
A fog chiller like this will work almost as well as a professional one. The professional fog coolers essentially blow the fog through an refrigerator evaporator.
Halloween of 1994, I had the police at my house 6 times, each time with them begging me to stop doing what I was doing... he so badly wanted a reason to arrest me, but could think of none.
Picture it: The doorbell was connected through an optocoupler to my computer's keyboard. Everytime the doorbell rang, there was a pause (as the stereo audio file loaded) then a loud scream played from a speaker (left) hidden in the trunk of one of the cars in the driveway. The right channel had a nasty kind of chewing sound, and it was played through a speaker hidden in the engine compartment of another car which was parked close to the door.
My roommate and I were car nuts, and we had a junked Toyota that we were waiting for the scrapyard to haul off. With the chain hoist, we put it on its side in the front yard, with a mannequin's arm sticking out from underneath. We hooked its electrical system up to a car battery charger and left some of the parking lights on, with a turnblinker flashing and the AM radio playing quietly inside.
I was working in the professional sound and lighting business then, so I borrowed a fog machine, fog chiller and 6,000 watts of Leko stagelighting.
The fog machine and the chiller from work went outside to provide a ground mist, but not too much. I needed for the kids to see, by the light of the flashing signal, the arm sticking out from under the Toyota.
The Lekos and my own fog machine were set up inside. The Leko dimmer pack was powered off the 40 amp 240V service to the stove outlet, and all 6 lights, at 1000W apiece, were pointed and focused to a point 1 foot outside of my front door.
And then there was the chainsaw. Beg, borrow, steal or rent a chainsaw. Take off the chain and protect the kids from the potentially sharp edge of the chain guide with a rubber edging like people use around the outlines of their car doors.
The Spectacle:
Mom or Dad would stand at the end of the driveway as Little Tommy would walk past the Toyota with the flashing lights and the arm poking out of the ground mist.
Little Tommy, dressed in his finest Teenage Mutant Ninja Turtles costume would press the doorbell. He'd hear the ring of the bell, then a couple of seconds later, the scream from the trunk of one of the cars he'd just passed. Gradually, he'd become aware of a wet chewing sound right behind him.
If Little Tommy was still standing at the door by the time I got downstairs, he'd be greeted to the sound of the door opening, and a wall of fog in front of him; invisible foggy blackness.
Of course, wearing black and a black ski mask, I'd be standing there watching the look of fear on the kid's face as it flashed on and off in time with the doomed Toyota's right turn. And then, just when we thought Tommy was getting ready to leave, Mike would kick the foot-pedal that turned on all 6kW of stagelights, focused right at the kid's face.
Blinded and disoriented, Little Tommy would start to retreat as I started up the chainsaw. And his first sight of me would be the silhouette, through the fog, of a black shadow with a running gas chainsaw.
Frozen, the kid would stand there, a deer caught in the headlights, as the chainsaw-wielding black shadow pressed the blade of the saw to his neck and revved the motor.
Of course at this point, the parent, standing at the end of the driveway, would feel that Little Tommy was in mortal danger, scream, drop the bag of candy, and attempt to rescue him from the chainsaw which would have already taken off the kid's head if it still had a chain.
The next morning, I had 4 broken windows, hate messages spray-painted onto the side of my roommate's car, the smell of two-cycle oil in my living room, and a hell of a lot of toilet paper and broken eggs to clean up. But I only had to give out 1/2 bag of candies, so I think I did okay.
Linux isn't ready for the desktop yet.
Fire and Meat. Yummy.