If you're like me, you are tall, dark and handsome, and have a thirst for bacon! Here is a quick, easy and cheap way to generate cold smoke for makin' bacon, smoked cheese, eggs, or for smoking your own malt for brewing beer.
We like to eat good, local meat, fruit and vegetables, and we enjoy making food from "scratch," or as close to it as possible. I've wanted to cure and smoke our own bacon for awhile, so I read a bunch of good articles on the Interweb.
I made this in about 2 hours, including photography, for about $25 total, including the pump. If you use simpler materials (coffee can/bean can, etc), it should cost a lot less and take you less time.
The idea came from http://www.homebrewtalk.com/f51/diy-venturi-cold-smoker-320916/, after viewing MissBetsy's excellent Instructable on a cold smoke generator: https://www.instructables.com/id/Miss-Betsys-Cold-Smoke-Generator/
This is a great explanation of the venturi principle and how venturi smokers workhttp://www.wedlinydomowe.com/smokehouse-plans/smokehouse-smoke-generator ,and their last diagram explains why I installed the smoking-blowing pipe at the top of the smoke generator, and why it is attached to the bottom of my smoke chamber (where the bacon and cheese live).
This type of smoker is known as a venturi-type smoker, and relies on the venturi principle.
The main focus is to generate cold smoke, you don't want to cook the food, just flavor and further preserve it. That means we want a slow burn, not a hot smoke. Hot smoking is a different process.
Issues with Safety: wear goggles when drilling, grinding, scraping, wiping, mincing onions, swimming, etc. Remember: sharp things are sharp, burny things burn and cutty things will hurt you. Be prepared, be safe, do it right, save $$$ on Emergency Room costs.
Careful with that open flame!
Do not leave the smoker unattended. Have a fire extinguisher handy. Only use this outside; dangers include fire risk and carbon monoxide (CO) inhalation, which leads to CO poisoning. That is a Bad ThingTM
Wear gloves, as stainless steel edges are sharp.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Materials Needed
- Cocktail shaker - stainless, Cobbler-style 3-piece - use PINT size if you can
- Fish tank air pump - for 10 gallon or larger tank - This accounted for over half the cost; get a used one free or cheap.
- Flexible plastic tube for pump, 1/4" OD (may come with the pump).
- Copper pipe:
- 1/2" x 6" long
- 1/2" x 2"
- 1/2" x 1"
- 1/4" x 8" long (1/4" ID, 3/8" OD) approx.
- Copper pipe fittings:
- 1/2" male pipe to 1/2" copper pipe adapter (1/2" MIP x 1/2" pipe) = MIP end has Male "Iron" Pipe threads
- 1/2" x 1/4" coupler (adapter)
- 1/2" tee
- Hardwood chips, pellets or sawdust for smoking (your choice)
- Optional: stainless "shoulder" strainer to fit inside bottom of shaker - this was an afterthought, and I'm not sure it does much.
Step 2: Tools Needed
- Propane or other gas torch
- Pipe cutter
- Wire brush - to clean copper pipe fittings
- Sandpaper (or pipe brush) to clean pipe ends
- Lead-free soldering flux
- Lead-free solder
- Tape measure or ruler
- Eye protection!
- Drill press, or hand-held power drill
- 1/8" HSS drill bit (High Speed Steel)
- 3/8" HSS drill bit
- 3/4" or 13/16" HSS drill bit
- Center punch
- Calipers for measuring (optional)
- Cold chisel (optional)
- Permanent marker (nice to have, will wipe off later)
- Die grinder or rotary tool (such as Dremel) (optional)
Step 3: It's a Real Strain
Let's eliminate the strainer. This shaker has mixed up its last cocktail, and we don't want to impede the smoke from exiting out the top.
On this strainer, there were three tiny spot welds - a well-aimed blow from your hammer might punch that strainer out, but I used a cold chisel and a big hammer. And eye protection!
Step 4: Bust a Fat Cap
It's time to
start continue destroying things! Remember that little top cap? You'll need to drill or cut a hole in its top to accept the male threads of the 1/2" pipe adapter.
We need to find the center of the cap, which is where we want to center our drilled hole. The fastest way is to look inside the cap, at its top - you can see the concentric circles of polishing marks. That will be close to the center of the cap's dome. Close enough for rocket work! You can mark this point with your marker.
Place your center punch in the center point of the cap's dome, then whack the punch with a hammer.
You may want to drill a pilot hole - a hole to guide the 3/4" or 13/16" drill bit. Or you could just go all crazy, and start with the 3/4" bit. Be sure not to hold the cap in your hand! (If you like your hand the way it is right now.)
If your male-threaded pipe adapter fits into the cap's newly-drilled hole, thread it in, or drop it in and secure with the conduit lock nut. (last picture)
Stand the cap upright; does the pipe adapter seem to be vertical? Fantastic! If not, you'll want to hog out that hole in the cap a bit more.
Tip: If you enlarge the cap hole too much, just use a second conduit nut on top of the cap, in addition to the one inside. It's okay if it's not a tight fit - this ain't rocket surgery.
Step 5: Measure and Cut Pipe
First, measure from one end of your copper pipe - choose an end that looks nice and circular and not mashed.
With your pen, scribe a line on your pipe at the 1" mark, the 3" mark, and the 9" mark; this will give your 1", 2" and 6" pieces of pipe.
Set your pipe cutter at the 1" pen mark on the pipe.
Option A: If your pipe cutter looks like the one in the first picture of this step, use the adjusting wheel to tighten the cutter around the pipe, so that the cutting wheel is right on top of the pen mark you made. Rotate the pipe cutter 360 degrees one direction around the pipe, then 360 degrees in the opposite direction. (i.e., clockwise, then counter-clockwise). Tighten the adjusting wheel, and rotate 360 degrees again, and back. Re-tighten, repeat, until you cut through the pipe.
Be careful, the edges of the copper pipe are very sharp, and you will need to deburr the inside of the pipe and maybe sand the cut surface. If you use sandpaper, be aware of little tiny barbs that will puncture fingers, right through sandpaper.
Option B: If you're lucky enough to have a little orange pipe cutter in the second photo, just open it, clamp it over the pipe at the 1" pen mark. Rotate the cutter in the direction indicated on the pipe cutter body by an arrow (only rotate this cutter one direction) until you have completely cut through the pipe. So easy.
Step 6: Prep the Pipe - Sand and Flux
Time to make it shiny! Using sandpaper or a plumber's pipe brush, clean the pipe fittings (both the T and the MIP-to-1/2" fitting). This removes surface corrosion from oxidation. Unless you do this step, your solder will not stick.
With sandpaper, clean the ends of the pipes; you only need to clean as much of the pipes as will stick into the fittings, which is 1/2". I always clean a little farther up the pipe to make sure.
Now is the time to dry fit everything; if it doesn't fit together now, sand your pipe ends a bit more, and maybe sand the mouth of the fittings. Also make sure your cocktail shaker cap and your horizontal pipe assembly are perpendicular/level/plumb. The pipes and fittings have a little bit of leeway, so you can move them slightly to make everything line up right.
Using the supplied brush or your gloved pinky finger, apply your lead-free solder flux to the insides of all fittings, and the outside of all pipes that will be soldered. This further cleans the copper, and determines where the solder will actually flow and stick.
Step 7: Torch It!
When your pipe sections and fittings have all been prepped, and everything looks right, start your little propane or mapp torch (you won't want to use a big ol' blowtorch or an oxy/acetylene welding/cutting torch here). Adjust your flame so the inner blue/white cones are 1/2" to 5/8" long.
Heat the pipe fittings, moving the torch slowly to heat all areas of the fittings until you hear and see the flux begin to boil. After a minute or two, your pipe fittings should be ready to accept solder. Hold the flame away from the pipe, and touch the end of the solder to the joint of the pipe and the fitting. If it melts quickly and flows into the joint, run your solder all the way around the joint.
If the solder does not melt and flow right away, apply more heat to the fitting. DO NOT heat the solder itself; even if some of it does flow into the joint, it will result in a "cold solder," and will have little strength and will probably leak. (Not the end of the world, here, since we're only flowing smoke and air, but cold soldering your house's water pipes will lead to flooding, cussing, and emptying of your wallet!)
Now that your pipes are soldered, drill out the shoulder/stop of the 1/2" x 1/4" coupler. Use the 3/8" bit in your drill while holding on to the soldered pipes. Be careful. This step allows you to insert the 1/4" pipe further than halfway into the coupling, which is important (I think) for the venturi effect.
After the pipes have cooled for a few minutes, inspect your work. If your joints look at least as good as mine, wipe the soldered areas with a damp cloth, to remove excess flux. This slimy, sticky residue will turn your hands green, and if left on the pipes, will make them icky-lookingTM.
Step 8: Base Mods
Grab the cocktail shaker cup, turn it upside down, and mark 3 or 4 holes.
Set the shaker cup on a piece of scrap wood, and center punch your marks.
Using a drill press (the safest way) or handheld drill, hold the shaker while you drill 1/8" * holes in its bottom. Wear goggles!
* note: 1/8" is just an arbitrary diameter - I have no empirical data to suggest this is the perfect sized hole (or the right number of holes). Experiment on your own, and let me know. After the trial run I may enlarge the holes, or increase their diameter, or both.
I marked, punched and drilled (4) 1/8" diameter lighting holes in the side of the cocktail shaker's base. Again, I have no idea what the ideal number or size of lighting holes would be. I did about what geniz on HomeBrewTalk.com did with his cocktail shaker (see the first link on the Intro page). I might end up increasing number or size or location of these holes, too.
If needed, you could later add a damper, using a small bit of sheet metal and a screw.
Step 9: It's the Final Countdown!
T minus 15: you are almost ready for liftoff. Now is a good time to take the cocktail shaker and the copper pipes and fittings and toss them in the dishwasher, or wash them in hot sudsy water, just to get any residual flux and gunk and dirt and stuff out. Don't forget the short section of 1/4" pipe.
I chose alder wood chips, because alder grows rampant here in the Pacific NW, and because the natives used it to smoke salmon, and I know it imparts wonderful flavor. Also it's not overpowering, like mesquite can be sometimes. You can use almost any hardwood or fruit wood, such as plum or apple, but stay away from cedar, pine, fir and softer woods; they have pitch and resins which will make your food taste nasty! As my sister Heidi would say, "It's the wood that makes it good!"
Next time I will use chunks, which are bigger and have less sawdust included. This would allow more air to pass through the wood, and it the fire would have a better chance of not being smothered. I'm not sure if the problem was the size of my shaker (hey, be nice, now!), which is double that of the pint-sized shakers (which I would recommend).
Step 10: Kick the Tires and Light the Fires!
Now, with your fire extinguisher close by, plus at least one sober adult, open the rocket (I mean "cocktail shaker").
Insert the stainless shoulder strainer in there like an upside down dog bowl. The idea is to allow some airspace below the wood chips.
Add 2" to 3" of chips or pellets (about 1 cup, or a handful)
Set the rocket/cocktail shaker on fire bricks, or make it some legs (future Instructable).
With your propane torch, light the chips through the (4) lighting holes. You should see smoke out the top within seconds.
Assemble the lunar module and rocket cone (cap and copper pipe).
Insert the 1/4" pipe about half it's length - I slid mine in about 4", just past the end of the T. Experiment with this positioning, as it may alter the venturi effect to some degree. You can write marks along the pipe if you want to keep track of this.
Insert the pump's plastic hose about 2" into the 1/4" pipe, and if it is loose, you might want to tape it. The vibration of the pump can wiggle the hose loose.
Plug the pump's electric plug into the outlet and watch the
Step 11: Final Approach
Now, I'll assume you've set up your smoking chamber or your outdoor grill or whatever needs a bucket-full of smoke.
Insert the end of the 6" length of pipe into your box or cabinet or grill or barrel.
Don your smoking jacket.
Add your cheese, eggs, malted grains, cured bacon...
I smoked the cheddar and cured pork belly (bacon) for about 8 hours.
Step 12: Mission Debriefing
After landing the Rocket, mission control (my wife and I) came to several conclusions:
1) The bacon was way too salty - I used 1/2 C maple syrup to 1/3 C curing salt. Next time I will soak the bacon overnight before drying.
2) After soaking and drying, it will sit in the fridge one more night to develop a "pelicule," or outer coating. This coating reportedly allows the bacon to absorb the smoke better.
3) I bought some pink "DQ curing salt #1" otherwise known as "Prague Powder #1" for next time - this is not Himalayan pink salt, this is only to be used for curing meat, and "contains 6.25% sodium nitrite and 93.75% sodium chloride as per FDA and USDA regulations" in order to prevent botulism! This is a Good ThingTM It is also supposed to preserve the bacon's pink color.
Side note on the DQ curing salt #1: If you are able to find local farmers who sell humanely-raised and -slaughtered meat that is not subject to horribly unsanitary conditions, you won't worry too much about botulism, but I'm going to try curing with this anyway. Nitrites are what "factory farms" have to use in order to counter all the bad stuff that can kill you, and these nitrites are known as "free radicals," which have been blamed for causing cancer.)
4) Water is a byproduct of combustion - and it has to go somewhere. In this case, it condensed in the cap, along with some of the smoke vapor, which combined to produce liquid smoke. I have a feeling this may be due to the tall cocktail shaker; that's one reason I suggest using a pint-sized shaker. The liquid smoke tasted just like the product you would buy in the bottle to flavor meats and such. The problem is that the liquid quenched the burning wood chips! So if I can find a way to harvest the liquid smoke without it extinguishing the rocket fuel, that would be a bonus.
Also, the liquid smoke found its way into every little cut on my hands and gave it an extra sting, just to be spiteful. And it colored my hands a weird yellowish-brown, like bruises. So, again, gloves are your friend (along with bacon, but bacon does not make good gloves, especially if you have dogs).
5) Because of the liquid smoke (see above note), the alder chips did not last long without having to be dumped out and replaced with dry wood chips. Contrast that with 1/2 cup of the mesquite pellets which I used for testing; they lasted for 2-1/2 hours without babysitting.
6) The smoked cheddar was fantastic - the smokiness did not overpower me, call me names, and take my wallet.
So, good luck, and may the porks be with you!
Participated in the