Before you get started making your own smoker, you’ll need to familiarise yourself with the “Venturi Effect”. There are complicated ways to explain this effect so lets jump straight to a simple analogy..
Q: If you’re driving along in the car smoking a cigarette and the window is slightly down, what happens to all the smoke?
A: The smoke gets sucked out the window by the air rushing past the opening.
Get it? Great! So that’s the Venturi effect and it’s what you’re actually aiming to emulate when building a venturi smoke generator. Using an air pump we create the fast moving air, which sucks the slow moving air (and smoke) from amongst the smouldering woodchips inside the smoke generator and sends it billowing into your smoking chamber!
It would be a good idea to gain an understanding of the various types of venturi smoker assemblies so you can choose for yourself which one to try. Polish Sausage Maker Wedliny Domowe has done an excellent analysis of the different types of Venturi smokers which I encourage you to read. The one we’ve chosen to build is very similar to the Straight Injector High Nozzle versions described in his article.
You can actually buy one of these units ready made. The “Smokai” is from New Zealand and is a fantastic product; we bought one to use for our new oak barrel smoker and it works flawlessly. Perfectly crafted from stainless steel, easy to use, easy to clean and likely to keep puffing smoke for years to come . Enough of the sales pitch from me though, watch the video:
After all the research I’d done online and then seeing the Smokai smoke generator in action, I sooned learned just how simple the concept really is. Not wanting to do those guys out of a sale or anything, but not all of us may have the spare cash to spend on an item like this.
Earlier this year I was in Melbourne and met up with a good friend and fellow enthusiast who was keen to start channeling smoke into his custom built bbq. With nothing else to do, we set ourselves the challenge to apply the Venturi principles to materials we had lying around in his shed. As I mentioned, we chose to build the straight injector high nozzle version that delivers smoke from the top, rather than the base of the unit.
Here’s how it worked:
Yes, that is a tin of dog food. Unfortunately the local mini-mart didn’t stock Golden Circle pineapple juice tins so this was the next best thing; washed and disinfected, you’d never know the difference. The tin was the component that cost us $3, the rest was just lying around.
Important Tip: Remember that the only way fresh air should enter the vessel is through the two small light holes at the base. This restricted air intake maintains the smouldering woodchips at a continually low rate of combustion. It helps to put a lid or cover on the tin aswell; a simple offcut of timber will do.
In the image above we’re testing the unit by blowing into the tube. Of course you’ll probably want to invest in a twin outlet aquarium pump to save your lungs the trouble.
So there you have it, a home made smoke generator that delivers hours of cool clean smoke. I would estimate the 1.2kg tin full of chips would supply a steady stream of smoke for up to 6 hours!
As always I welcome your comments and if there is any more information I can give you to help, just let me know.