Miss Betsy's Cold Smoke Generator

Fall is already here, the days are cool and unlikely to push the thermometer over 70F, which means perfect weather to make bacon!
Last time I made bacon I used a pretty complicated arrangement of a stove and stove pipes to cool the smoke and guide it into my smoke chamber; this time I made myself a small and easy to maintain "Cold Smoke Generator".

Materials needed:
16/14 oz. can
36 oz. coffee can
#6 metal screws
8" piece of 3/8" iron pipe
Several brass and copper fittings and pipe (get your idea from the pictures)
1/4" O.D. plastic hose
Some kind of feet (I used 3 shelf brackets) Make sure the apparatus doesn't tip over and set your house on fire!
An old aquarium air pump. (Even a new one isn't too expensive ~ $20).
Wood pellets or Hardwood! saw dust to fire the thing up.

Tools you should have and which will make completion of this project a lot easier -_^

Drill / Drill-stand
Assorted drills
Screwdrivers
Pliers
Hack- Jigsaw
Metal file

Step 1: Main Parts

I decided to use a 16oz. can as burner chamber and a coffee can as reservoir for the wood pellets. Should be available in every household.

Step 2: Attaching the Burner

Put the smaller can centered in the middle of the bottom of the coffee can and mark with a pen. I divided the circle in 8 pie shaped pieces and drilled a hole in the middle of this circle. With the help of a jigsaw I cut along the lines so that I could connect these 2 cans. Bend the sheet metal up, set the smaller can on top and use metal screws to secure it.

Step 3: Preparing the Venturi Tube

In my parts drawer I found this 8" piece of 3/8" galvanized iron pipe. With the help of a drill and a file I made a slit roughly in the middle. The plastic hose, coming from the aquarium air pump, was attached with some connectors and brass fittings. You will have to play around a bit depending on what you find.

Step 4: Preparing the Burner

In order to make the burner work, you will have to drill 3 holes; 2 to push the venturi pipe through, and 1 to ignite the hardwood pellets and provide oxygen for the embers. I used a 9/16" drill which is about the right size for the 3/8" pipe to fit through snug.

Step 5: Assembling the Cold Smoke Generator

I had 3 shelf brackets at hand to use as feet which works great but I am sure there are plenty other ways to stabilize the smoke generator. Just make sure you don't set your house or garage on fire!
In the pictures you see a prototype where I used a drain strainer as bottom for the burner. I found out that this didn't work so well so I made the version with the 3 holes in the burner. This latest version works at least 2 hours  without maintenance which is sufficient.

Step 6: Trial Run

The cold smoker doesn't need much wood pellets to run and produce sufficient smoke. What you see is plenty for at least 8 hours of operation which will soon produce some fantastic bacon. (I will tell you about that in a separate instructable!)
Watch a short video of the smoker in action:

Comments

[DBPlunk]

Did a double-take. I have that same caliper with almost the same corrosion.

[Maxguitard]

Did you drilled hole in yhe bottom of the can even you didnt use the drain strainet?

Im concern about the ashes

[MissBetsy]

As you can see I set my smoker up on the concrete pad; if you are concerned put a empty tuna can or similar under the smoke generator to catch the small amount of ashes it produces.

[wildbill001]

Any idea as to the amount of air the pump is putting out? I'm using a pump for a 20gal aquarium and it doesn't seem to produce/pump enough air to keep the smolder going.

[MissBetsy]

Sorry I don't :/ - the pump was an old 1 that came with my 55gal tank

[MonicaP12]

OK, I am new to smoking and really only need to smoke some ricotta since I cannot buy ricotta affumicata (smoked ricotta) in the USA. My question is, where do you place the item you are smoking? Inside the large can? I really would like to make this because I live in an apartment and it looks small enough for what I need to use it for. Also, can someone make a suggestion for an alternate pipe since the galvanized pipe can give off toxic fumes?

[MissBetsy]

I'm afraid I have to disappoint you :( What you see here is just a "Smoke-generator". For smoking cheese or meat you need a "Smoke-chamber" as you can see here: https://www.instructables.com/id/Miss-Betsys-Excellent-Bacon/ - unfortunately I doubt that you will fit that in your apartment. You might find the right thing by looking around here on Instructables. A word of caution though, smoke might contain toxic particles!

[vocalpatriot]

any cheap grill with lid would serve well for a smoke chamber...heck even a zip-lock bag would work to cold smoke cheese and such.

[MichaelW157]

Black iron, or gas pipe, available at most hardware's and,.. I got it at LOWES....It comes in precut sizes....

[Dominic Bender]

I have been considering smoking things for a while now, but never got very far. Your generator looks simple enough, although I have yet to come across a coffee can that size.

[MichaelW157]

Gallon paint can , ask at store for an empty one, not used..???

[vocalpatriot]

lowe's and the home despot both sell new, empty quart and gallon sized paint cans and lids.

[MissBetsy]

As I found out, it is not really necessary to use such a big can as a reservoir, as the smoker doesn't use very much pellets / sawdust. In need, I am sure, a neighbor or colleague at work could help out with a coffee can.
In any case, good luck!

[GregS3]

We just bought a house and inherited several dozen gallon sized paint cans. Properly cleaned, one of those should work as well as a coffee can

[Branchinbrighton]

Can anyone explain to me why galvanized pipe in the can and copper pipe exiting? Couldn’t I just use all copper or All galvanized? And the comment regarding the Venturi effect, does that mean the copper isn’t soldered and can be moved in and out of the galvanized pipe?

[cutshopguy]

Hi Miss B,
love your work. Just a question about how you fire up your wood, whether its hardwood pellets or wood chips or whatever, to produce the smoke? How do you get it to the smoke point and how do you maintain the temperature so as to continue producing smoke?

[MichaelW157]

You could put a soldering iron in the side hole till the pellets start, clean thoroughly, or buy a cheap ( Harbor Freight ) one , as lead on the iron is no good,.. but for just starting and not leaving it in should be OK...

[MissBetsy]

In front of the can is the firehole as described in the instructable. The hardwood pellets are ignited there with help of an blow torch. The aquarium pump is used to create a Venturi effect in the tube inside which means it sucks air (oxygen) in and keeps the ambers ambering and blow out the smoke on the other side in direction of the smoke chamber. Everything clear now?

[texaskathyy]

How are the ashes removed?

[MissBetsy]

Ashes fall through the bottom holes, can be cleaned out through the fire-hole or are removed when the fire goes out and the smoker is emptied and readied for a new run.