Haze from a smoke machine

[cedd]

Hi all

 

I have a very cheap sound lab smoke machine like this one;

 

http://www.soundmastersdirect.co.uk/cgi-bi...owprod_SLBG002A

 

Has always done the job I've needed doing pretty well and despite the cool/heat cycle, always seems to be ready when I need it. Infact I've been wondering about making a simple DMX controller for it.

 

Anyway, I now have the need for a hazer, firstly for some small theatre work and also for when I occasionally DJ. The smoke output from this unit is a bit heavy for my needs.

 

Being a yorkshireman, I'm not too keen on buying a new machine.

 

I have in the past made up a "spray bar" type arrangement (40mm drain pipe with end caps and lots of holes drilled in it) which does help, but still isn't the same as haze.

 

So....

 

Is there a fluid I can put in this unit that will make a haze output? Other threads on BR suggest a fan but I'm keen to explore other options. I'm not sure what type of fluid this machine takes as it's in an unlabelled bottle and all the associated adverts linked to this machine don't specify.

 

I might be talking rubbish and that kind of output may not be available from this type of machine, but it's worth asking!

 

Also should I be using a different type of cleaning solution on this one what with it being a cheapo unit? A friend put some strawberry smoke essence in there and it really does destroy the illusion of a seedy London Street mid-play!

 

Cheers

[Jamtastic3]

With something like this, the best alternative is (like what you've heard) a fan. The bigger the fan, the further the output goes and so the finer the output but the louder the noise from the fan. You are best creating a 'circling' of smoke around the room rather than have a the fan point directly onto stage so the smoke disperses well.

 

Hazers already have fans built into them, and so the output is different due to this (and other factors)

[the kid]

Cleaning I will leave to other people to give a fill reply to, but there are some topics on it, I have used Ionised water just to clean through the pipes, not sure how good it is for smells.

 

 

I typed and read the post again, and you have said not keen on a fan. They do work the density is different and I'm sure the linger time is as well, been a while since I used fog as haze, if anything fog as haze might look nicer if it has that thickness to it it might add that extra "seedyness".

 

After what Jam has said when I did it I had the fog facing off but up stage, and the fan on stage but down. (See below, I got arty the 8's are smoke puffs that shouldn't be there because of the fan)

 

\ fan

8 8 8 8 8

/ smoke

[cedd]

Thanks for the replies so far, a fan does seem like a simple fix, but the haze and smoke just seem to "hang" slightly differently. My main concern is making beams from movers visible rather than having "smoke" itself.

 

Just to clarify, the street scene isn't actually this show, it was a previous instance when Bill Sykes' entry was accompanied by the whiff of strawberries!

 

I suppose the question really is the difference mechanically and electrically between hazers and smoke machines. As already mentioned, hazers have fans, and I know my smoke machine works in a slightly different way to most as it has a cool/heat cycle and I'm not sure if it uses the normal fluid. If anybody knows what type it takes it'd be very helpful. Hence the question about cleaning this individual machine and if I should or shouldn't use the off the shelf cleaning fluids available in it.

 

Best bet if a haze output isn't available from this machine could be a long spray bar with occasional doses of smoke applied when it won't be noticed so I keep up to the haze level.

[niclights]

Again, best you can do is use a fan. In conjunction with frequent short duration bursts it's the closest you can get - maybe a timer? If you can find fluid that is lower density/concentration than was designed for your machine then you should be able to safely use it and get a thinner output, but you cannot avoid the fact that a hazer will be designed for constant output and your smoke machine will not.

 

/edit: you posted as I typed. There is no difference in hang time unless hazer is mineral oil type. Otherwise the fluids are the same (water/glycol) and produce same size particles. Water/glycol approx 20 micron, mineral oil approx 1 micron. Glycol based hazers are the same as 'smoke' machines but designed to heat/output constantly. Clean by pumping de-ionised water through (not ionised as above!). Be careful when doing this.

[Jamtastic3]

The kid, I'm guessing it didn't work for you? :)

 

You need to have the fan output and the machine output in the same direction. So I'd place the smoke machine and fan in the wings at the back with the output facing the cyc/back/wall. It takes a while to get right both direction and smoke output.

 

> ---- Smoke

>IIIII Fan

 

or

 

>-- >II-II-II-

 

Fan in front of smoke

[the kid]

Actually it did for what we wanted and it was a .... I cant remember the name but it had a bucket in the front for the ice, lifting the lid and the output on low/medium with a fan produced a reasonable haze.

 

Also it was practically next to the output.

[cedd]

Fair enough, I think a fan will have to be the way to go. I might even make up a duct with a cpu fan in the side so the smoke and blown air mix and are forced out of a nozzle. Little bit of sheet metalwork and tig welding practice!

 

Thanks for the input. CPC do have the ACME brand that lists several different smoke densities depending on which fluid you buy, all for the same machines. Might have a play.

 

Cheers

 

C

[DavidLee]

Up to you whether to risk putting it in your machine - but Rosco manufactures a range of water based fog fluids .

 

Fog Fluid, Stage & Studio Fog Fluid (rapid dispersal) and Light Fog Fluid.

 

In normal use, Light Fog Fluid produces a lighter fog density, which may help you, but you need to use compresed air to produce a true haze effect.

 

Rosco Delta Haze Fluid is purpose made for the effect but is sold specifically for the new Delta Hazer so it may not be compatible with other fog machines.

 

Try emailing Rosco for advice - they are usually very helpful.

 

David

[Brian]

This might be worth a read. It comes from a Rosco technote available in full on their website...

 

Ducting Fog

 

It is not always possible to place the fog machine near the exact location where the effect needs to occur. The answer is to use ductwork to direct the fog. Flexible ducting can be used, but it should be of heavy construction. Most dryer hose is too lightweight to stand up to the rigors of theatrical use. If needed, rigid PVC pipe can be used.

 

Whether flexible or rigid ductwork is used there are some points to remember. For most applications the minimum diameter duct used should be 4 inches. When fog is constricted, it tends to recondense into fluid reducing the output and creating an unwanted residue. Likewise, recondensation can occur if the ductwork is placed directly over the front of the fog machine. The aerosol is created when the "flashed" vapor mixes with fresh air. If flexible hose is used, an openwork frame should be used to keep an air space in front of the machine (see below). If rigid ductwork is used, simply keep the front of the machine 3-4 inches from the duct. If the fog needs to travel long distances in ductwork, a squirrel cage fan can be added. The fog should not come into contact with the fan blades. The air should be added through a "Y" connection.

[dbuckley]

Smoke machine with big fan behind gives an effect similar but different to a hazer, as has been noted

 

http://www.davidbuckley.name/pix/cinders_244_lores.jpg

 

Martin DMX smoke machine, which was poked to 20% output for 15 seconds every 1:10 apart.

 

Needs to be a big fan; I use Honeywell 18 inch jobbie, like this specimen, set on low.

[cedd]

Awesome, thanks for the replies. I have some time to play about a bit, so I'll see what happens and get back to you.

I've also just ordered the bits to make a DMX interface for it (it's just a closing contact brought out of the unit by an IEC -as discussed regarding how safe this practice is in another thread).

 

Only issue is I can only do testing in my double garage as it's too windy outside and a long drive to the theatre, so you get about 10 seconds of squirt before you have to run away coughing and spluttering!

[son of lx dad]

as mentioned above pointing your machine with fan at a wall close by and using it to bounce the smoke into the room is an older theatre trick. It can help reduce the billowing effect and take the 'energy' out of the initial blast and will remove some of the more energetic particles. The wall can end up a bit greasy though.

[Russ83]

CPC list a couple of Haze machines but with limited stock (linky). Be carefull though as the fluid they list with that item is not suitable and will actually bugger the pump . I will be giving them a call about that later today.

 

In the past I've always used a basic smoke machine pointing at an office type fan angled slightly upwards and got pretty good results.

[Thegael]

Along with a decent fan, have you considered watering down your smoke fluid? Use de-ionised water, available from pretty much any Auto parts store. Make sure it's a water-glycol based fluid though. We used to do that, and it makes a much thinner smoke, which could be good to use for a haze.