making your own fog juice?

[BigClive]

The Radiance hazer is interesting in that it acknowledges that many heater block machines inevitably clog up. It gets round this by using a novel design of heater block that has a series of chambers in it and can be routinely opened for internal cleaning.
http://www.ultratecfx.com/Libraries/...nual.sflb.ashx

The main difference in using a hazer and smoke machine in a nightclub is that DJ's will inevitably use a fog machine excessively to exert their presence. With a haze machine they can't really do that, so the fluid lasts a lot longer.

[norty303]

The main difference in using a hazer and smoke machine in a nightclub is that DJ's will inevitably use a fog machine excessively to exert their presence.

The Smoke Factory/Look/HazeBase hazers will also allow you to exert a presence - all night and without interruption if desired!

I recently had to do some work on my Smoke Factory Tour Hazer as I though the heat exchanger might be clogged (it turned out to be the air pump). One of the tests was to see if you could blow down the pipe connected to the heat exchanger (read heating block, although in the TH2, the pipe wraps around the heater in a coil, rather than be sandwiched and snaking). To my surprise the pipe is actually VERY large bore, and it was incredibly easy to blow through, not something I've ever found in a smoke/fog machine (even with the restricted nozzle removed), and I suppose this helps avoid clogging problems.

I guess in a [non-cracking] water based hazer, you don't need the pressure in the heater to force the fog out as a jet, as you have both an air pump (to smooth fluid delivery) and a fan (to propell the resultant fog)

I'm still curious how they get such longevity from a gallon of fluid (~£40 - I started a bottle in April and have done 4x 3 day festivals and about 4 all nighter events and am nearing the end only now) when i also have cheaper hazers (albeit without smoothing air pumps - 'fazers' essentially) which use up their fluid at 4 times the rate (I use a generic HD fluid of good quality, at just over £10/gallon - so works out about the same cost overall)

The big difference between the 2 (which i mentioned previously) is that the Tour Hazer seems to leave no residue on kit, even if its directly in front of the nozzle (such as a lighting lift on the stage), so it either has a much more efficient and complete way of vapourising the fluid, or the cheaper ones never quite heat the fluid enough, resulting in a lot of raw fluid being ejected.

[Stiffler]

The main difference in using a hazer and smoke machine in a nightclub is that DJ's will inevitably use a fog machine excessively to exert their presence. With a haze machine they can't really do that, so the fluid lasts a lot longer.

Personally, I don't think there is any place for a smoke machine in a nightclub, or any entertainment venue for that matter, for the reason you stated above. Regarding hazers, I have run the Radiance in the same venues where I have also used a Chauvet hazer, and the Radiance still uses substantially less fluid. I have also seen venues use cheaper haze fluid in the Radiance to save money, but instead went through twice as much fluid. There is differently some high level chemistry going on in their haze fluid.

[buffo]

some fog juice uses a very small amount of a type of alcohol to act as a stabilizer, a surfactant, and an anti bacterial agent all in one.

Your organic chemistry background is showing, Karl! My money is on tert-amyl alcohol. Am I close?

Anybody here smart enough to wrap their head around how all those fancy hydrocarbon chains interact to make the perfect fog juice with the perfect particulate size? I'm not and I'll admit it.

I think you'd need to be a PhD chemist with a few decades of experience to answer that.

a lot of glycols can look the same or be confused with each other even with high end test gear that is not specifically calibrated for the task. The manufacturers know this, and use this to their advantage to disguise which glycols they are really using as well as their ratios.

Agreed!

All glycols will potentially break down when the remnants of the vapour are trapped in the labyrinth of the heater block. The quantities of "burnt" glycols are tiny and the acroleins that can potentially be produced are negligible compared to the smoke from frying pans, barbecues or cigarettes.

Glycols can produce acrolein when cracked, but only in very minute, trace amounts. You're far more likely to form an organic acid like oxalic or lactic acid.

Glycerin, on the other hand, readily decomposes into acrolein. (In fact, Acrolein is the primary thermal decomposition product of glycerin.) Couple that with the high toxicity of acrolein and you can understand why this issue is being discussed so forcefully.

As for frying pans, I don't know too many people who fry their food in glycerin. And while you can produce acrolein from corn oil (or sunflower oil, or olive oil), it is by no means the primary decomposition product. Again, we are not talking about acrolein as a risk with glycol fluids. Only with glycerin fluids.

Cigarettes, on the other hand, are a good example of a source of acrolein. But let's face it: if you're smoking cigarettes, you're not exactly worried about the health of your respiratory system, are you?

And if you work in a club that allows cigarette smoking then the smoke machine is really the last thing you should be worried about.

False dichotomy. First, you can (and should) be worried about both. Second, if you are the one operating the fog machine, and you are using home-made glycerin-based fluid without a scavenging or stabilizing agent, you are placing the patrons of the club at risk. Not cool.

All the glycol fogs are by nature quite hygroscopic and tend to absorb moisture from the "mucous membranes" of the human body.

All true. Still, glycol fogs are less likely (far, far less likely) to produce acrolein, even in a thermal runaway scenario. That's why they are preferable to glycol-based fluids, which is the main point of this discussion.

I think this thread has been a bit to harsh with the toxin scare-mongering. If a really harmful level of acroleins was being generated then the machine would be putting out a jet of acrid smoke and people would naturally stop using it because it would STINK.

Do not confuse the use of a commercial fog fluid that contains glycerin with a home-made one. There is a significant difference. (Unless you've been adding stabilizing agents and testing your home-made fluids for hazardous thermal decomposition products with your in-home GC-MS unit, that is.)

Furthermore, do not forget that by the time you smell acrolein, you are already well above the point where it is causing problems for your respiratory system.

Finally, most commercial fog fluids today have moved away from glycerin in favor of glycols.

Have you ever fried up some food and the smoky frying pan makes your eyes sting so much that you have to leave the kitchen?

Again, cooking oils do not produce acrolein in any significant quantities when cracked. The smoke and stench you are speaking of in the kitchen is not due to acrolein. (Or if it is, you are a REALLY bad cook!)

For professional use in public areas it's a much better idea to use bought fluids simply because that immediately exempts you from liability regarding the fluids contents. Proper smoke fluid is readily available cheaply now as high profile brands or more generic universal ones.

This is the main idea. If you want to make your own fluid for use in your home, and you understand the risks and feel it's not something to worry over, that's your call and you have every right to do what you want. But as soon as you plan to expose the public to your fog, you owe it to them to use a professionally-prepared fluid. That is all we've been trying to convey. If the thread comes off as scare-mongering, that's unintentional, but given the shocking lack of knowledge upon some of the people in this thread, we can perhaps be forgiven for stating our case a bit more forcefully.

Adam

[BigClive]

Just a thought... Someone mentioned a fogger going on fire.

All fog machines should have a one-shot thermal fuse in them that will trip if their block exceeds the rated temperature by a modest margin due to failure of the thermal control. It's not uncommon to have these trip randomly in machines that have been running for a long time. Particularly if their air vents are blocked by surrounding equipment. They should ONLY be replaced by a thermal fuse of the same temperature and NEVER be shorted out as a "quick fix" because quick fixes become long term fixes if the problem has gone away.

[Laser Wizardry]

" 15 characters"

[kecked]

I never found a stabilizer in any fluids from rosco at least that I tested and a cheap one from a drug store. Actually the stuff even in the cheap one was reasonably pure. There were a few real small peaks I didn't identify on the gc but we are talking like 0.5% stuff. It could well be noise or crude from a previous run. Since the stuff most common is food grade this does not surprise me.

[kecked]

I didn't find anything but water and a grouping of different weight glycols. They have some poly glycols like PPG poly proplylene glycol. Not sure if they meant to do that or it just occurred but they may be adjusting the properties of the fog by the use of the different weight polymer versions of the glycol which makes sense. A heavier glycol makes a heavier fog which makes it stay low to the ground but with a shorter hang time.

[buffo]

I think the point he was trying to make was a lot of acrolein is produced in things like frying pans.

That's created in the food as a result of fats and sugar alcohols breaking down under the high heat. As discussed above, the limit for ingestion of acrolein is much higher because it's readily broken apart by stomach acid. We're more worried about airborne sources, of which frying pans are a poor source. (Unless you have the runaway deep-fryer scenario, as listed in the incident with the two dead kids above.)

It doesnt matter if glycerin is involved there or not.

Yes it does. Glycerin is the one chemical that converts most readily to acrolein. Glycol, corn oil, and other esters are far, far less likely to form acrolein.

how do you know there's any stabilizing agent, etc. in any commercial fog juice to begin with?

As mentioned above by several posters, the "other" category in the fluid is your stabilizing agent. Though this really is more applicable to older, glycerin-based fluids. Newer glycol ester fluids do not need it (apart from the addition of a weak organic base to absorb any oxalic acid that is formed).

Regarding the odor threshold, using the data in the link you provided, even a best-case scenario where the odor detection limit is .48 ppm, you are still above the concentration where irritation begins (at .34 ppm). Furthermore, the concentration for irritation in your link is one of the highest I've seen. Look back at the other links posted above and you will see that most other studies show problems at far lower concentrations. (up to a factor of 100 lower, in fact.) Likewise, the concentration where acrolein is considered to be immediately dangerous to life and health (IDLH) is only 2 ppm in air.

ive moved to glycols as suggested by you guys

Smart move.

I never found a stabilizer in any fluids from rosco

Pretty sure Rosco fluid is a mix of propylene glycol and other esters. I don't think it has any glycerin in it, so it shouldn't need anything to scavenge acrolein. At least not anymore. (The older fluid from the 90's may have contained glycerin.) Admittedly it's been a while since I looked at the bottle though. (I don't use it anymore, but I think RGB-Gas still has some in his shed...) There might be an organic base in there to tie up any lactic or oxalic acid though.

There were a few real small peaks I didn't identify on the gc but we are talking like 0.5% stuff.

It wouldn't take much. 1 ppm of something like ethylamine would probably be enough (that's a couple drops in a full gallon of fluid). Finding that on the GC would be maddening though. Even HPLC would be a chore...

Adam

[mixedgas]

The stabilizer would likely be PVA, Poly Vinyl Alcohol. Water soluble, nicely binds miscible fluids, safe, decomposes easily. Makes for a wonderful viscosity control.

Steve