Guerrilla Outdoor Smoke Machines.

[Bob Hart]

Okay. Any clever fellas out there made one of those outdoors smokers out of a two-stroke yard blower?? There is apparently a smart trick of winding brake pipe inside the muffler and connecting up an extra crankcase pulse pump to move the smoke oil through the muffler heat exchanger then into the blower airflow as smoke. Any advice appreciated, plans or photos appreciated even more.

[Warren Kawamoto]

It really sounds like you already know all there is to it, just connect the brake tubing exactly as you describe, with the end of the tube directly in line with the blower to disperse the smoke.

I used to make my own smoke by using empty soup cans. Put a 3 or 4 glowing charcoal briquettes inside, then add a couple drops of cooking oil on the charcoal. Billows of white smoke is the result. Since the smoke comes out from the small can, it can be moved around easily with tongs. Do not use indoors though.

[Bob Hart]

Regrettably, the only knowledge I have is the general principle. I was curious if anyone had a working specimen. The nearest I have seen on the web was a lawnmower engine apparently used on a War outdoors set. How they got that to work was not apparent. It might have been a moribund example so whipped that it was burning its own engine oil or a stiff oil/fuel mix was running it.

On a larger scale, Australian Bob Bosisto did something similar with two Holden ( GM Australia ) motors driving industrial fans as wind machines.

Apparently after ruining a fair number of cast exhaust manifolds by drilling them full of test holes to feed smoke fluid in, he found the elusive place where paradoxically, there is a predominant suction in an otherwise pressurised environment. He was feeding the material into hot exhaust gases from a loaded engine.

The very much smaller two-stroke engines apparently do not produce enough heat to reliably evaporate smoke fluid poured directly into the exhaust stream and through some idiosyncracy sometimes suck the raw smoke fluid back into the cylinder at certain power settings, the fire gets put out and the engine understandably stops.

This is apparently why some sort of heat-exchanger coil has to be built into the muffler. Another reason is apparently to separate the actual engine exhaust and the smoke source. Two-stroke exhaust is not very pleasant to the senses and likely unhealthy as well.

[Battle Vaughan]

You might think of a gadget like this, assuming it's available where you live. I have used an earlier model of this device for its intended purpose, not for fx, but it put out a satisfying amount of smoke: Amazon.com: Burgess 1443 40-Ounce Outdoor Propane Insect Fogger: Patio, Lawn & Garden

[Chris Medico]

Originally Posted by Battle Vaughan

You might think of a gadget like this, assuming it's available where you live. I have used an earlier model of this device for its intended purpose, not for fx, but it put out a satisfying amount of smoke: Amazon.com: Burgess 1443 40-Ounce Outdoor Propane Insect Fogger: Patio, Lawn & Garden

I have used one of those for FX fog and it does work. You have to use the oil based smoke fluid and not the glycol based fluid.

Make sure you don't ever use it with the bug fog fluid if you are going to use it for FX. Label it for FX only.

[Bob Hart]

Battle Vaughan and Chris Medico.


Thanks for that info on the insect fogger. These are not commonly used out here. Maybe they should be as we do have a mosquito-born disease problem.