Simple, Cheap, CO2 Regulator





Introduction: Simple, Cheap, CO2 Regulator

This simple CO2 regulator is used to slowly release CO2 gases from the fermentation process of wine or beer using water and a few parts that can be found quite easily. It works by allowing CO2 to get out of the fermenter without permitting oxygen to enter. If oxygen was to get into the fermenter, it would stop the yeast from making ethanol alcohol.

Step 1: Gather the Parts.

Parts that you will need:
-One Cork
-3 inches of 3/8 inch hose
-Hot glue or other sealant
-A water bottle
-Clear film canister (usually available at any place that develops photos, ask for one)

Tools that will come in handy:
-Drill with 3/8 inch and 1/2 inch drill bits
-Hack saw
-Bench vice
-Belt sander/metal file/sandpaper

Step 2: Drilling and Fitting

First drill the 1/2 inch hole in the exact center of the bottom of the film canister. It should have a little dimple where the tip of your drill bit will sit nicely. Next, drill a 3/8 inch hole through the clamp. A bench vice helps. Once the holes are drilled, fit your tubing through the hole in the cork. You will need to calibrate and trim the tube, but we will get to that later. Next force the cork into the 1/2 inch hole in the bottom of the film canister a bit more than 1/4 an inch. After you these parts put together, you will need to seal the cork into the canister. I used hot glue but other sealants should work.

Step 3: Constucting the Cap Fixture

Now we need to construct the part that will act as the one way valve. You will need to sand down the cap to get rid of the lines or grip. To do this, leave the cap on the bottle and start sanding away. A belt sander would be very useful but if you do not have access to one of these you can sand it or file it down. You need to make sure that there is enough room between the cap and the sides of the canister. If it is an air-tight seal, it will not work properly. I just took the cap off and dropped it in and kept testing it. After you get it shaved down enough, screw the cap on tightly, remove that little ring of plastic, and cut the bottle right above the lip on the bottle. If you have no idea what I am talking about check out the picture. You will also need to sand off the rough edges.

Step 4: Putting It All Together and Calibrating

Lastly, you will need to punch a small hole in the cap in order to let out the gases. To calibrate your regulator you will need to adjust your tubing. Make sure the tube is nice and straight and protrudes about an inch into the canister. Fill it up with water to the top of the hosing and drop in the cap part you just made. Push down until the gas is released and some water comes out of the bottom, lowering the cap to a bit more than halfway. Pop on the cap and SLOWLY blow into it. If you blow to hard the cap will just stick to the top. You just have to slightly exhale to get it to work. I've also attached a video of it working on a jug of fermenting grape juice. Enjoy and I hope this was helpful!



    • Stick It! Contest

      Stick It! Contest
    • BBQ Showdown Challenge

      BBQ Showdown Challenge
    • Backpack Challenge

      Backpack Challenge

    46 Discussions

    I've done that with a balloon. I've also done the tube in the water when the fermentation was going crazy and clogged the airlock.

    Hello Mate, Living in the jungles of darkest Thailand we have no brewing shops here, Probably illegal anyhow. Maybe thats why there are rice beer and spirit brewing facilities hidden away all over!
    Anyhow, I made an airlock from a piece of clear plastic tubing with a loop in it, secured by a cable tie, then glue gunned into the cao or lid of my fermenting vessel and then a piece of cotton wool in the top. As its so bloody hot here I sometimes use a drop of steralising fluid in the airlock water.

    Enjoying the comments by the way.

    WARNING!!!!!!! I have a degree in photography and leaned the chemical components in film and you never, never, never ever want to use film containers to store food ,come in contact with food, or pills. depending on the company and type of film you could slowly be ingesting silver "cyanide" and the other chemicals are nun to friendly either. use only for objects you will handle but never come in contact with food or your mouth or eyes!

    Silver cyanide is mainly used in the developing of film but the canters get reused over and over. when I worked in the photo department at walgreens we would ship them back and now that film is going out of style less and less is made and the containers get reused over and over this is not a food quality plastic either which can contain led.

    Please don't tell me "well I have been using it and I am still fine" many of a photographer has had large health problems down the line from the chemicals we used to use and we didn't drink them either so for your safety please find another container to use other than film canisters

    1 reply

    But you're not drinking beer out of this. It just creates an airlock to let CO2 out and keep oxygen from getting in. It doesn't come in contact with the beer/fermenting liquid.

    This is not a regulator but a waterlock. It does keep oxygen out of the container, but it does nothing to hold pressure in as a real regulator does. But there is no use in making a waterlock. They cost less than a dollar at homebrew stores.

    However I do like the idea of reusing a cork and drilling it out to accept a waterlock. Rubber corks are always better and cheap, but sometimes you just don't have one on hand to fit the neck of the container you want to use.

    great tut! i have exactly those parts! was looking for somthing simple without the rubery/latex taste.
    Also i have builders hotglue( the yelllow kind that you see in electronics that give even a soldering iron a hard time to melt).

    i know the bad replies were old, but let me say this. The point of this ible is for the quick emergency "i have those parts!" times. This goes for all 'ibls...

    1) you are a moron to think he expected anyone to go and buy the required materials. Why would you if its going to be more than pro price?
    2) This works well for your first batch or even a "oh crap my airlock broke and ebay is my only option!" moments. If you dont feel comfortable reusing this then dont.
    3) lets see your diy project? is it perfect? does it meet all saftey/health department/fcc/fda/rca/att/ymca requirements? i diddn't think so. its diy. it never will. stop being baby and crying. girly men.
    4) this is an advanced method of control compared to what most of our ancestors used. they lived. oh right some out there have to try and control every single cell of bacteria they find. problem with that is we have more diseases now and are less immune to them because of our so called "sanitized lifestyle" I ate mud pies my sister made me. i see parents that freek and hose down their kid then give them an antibacterial bath when ever their kids touch dirt. a little germs wont hurt anyone. unless you have aids...

    nice Instructable, it gives me somthing to make soon. yay. its a shame that peep on here are giving you a hard time. it is a good design to make out of stuff laying around the house! thats the point.... its a home brew...

    1 reply

    Yeah :/ oh well. They do make a good point about it not being sterile however. And you can get them for really cheap at brew stores so you don't really save a lot of money. I basically made it to save me a trip.

    Though this is a resourceful design from common household items, the device is an airlock or fermentation lock not a co2 regulator. 

    personally i always use a new cork without any modifications, one that is not meant to seal in liquids. the pressure inside the bottle forces co2 out but does not allow o2 in. cheap and easy. no work required.

    I've brewed beer, made wine, and even moonshine. In addition, I have spent time learning about the history of each. While there are flaws in this method, exactly what do you all think people did before the time of plastics and modern sterilizing chemicals? Wine has been made for thousands of years. I commend Dandeman for his efforts even though I personally use cheap, mass-produced airlocks myself. As for the cardinal rule of Sterilize, have you ever heard of Lambic beer, originally fermented in open vats so that the local native yeasts could provide a wonderful citrus character into the beer. In general, some people need to do some research before criticizing the people that put instructables up. If you don't like what someone else puts up, do your own instructible of what you consider to the the "right" way, otherwise, please be quiet.

    8 replies

    Thank you for the nice comment! I was so discouraged when I first made this, no nice words were said... thanks for the defense.

    No problem. If you wanted to improve the execution you could use a rubber stopper with a piece of hard tubing then then drill a slightly smaller hole than the tube in the bottom of the film cannister then push the tube in. that might be watertight, then you could add just a little silicone caulking on the outside where the tube contacts the canister. That could all easily be dipped in bleach water with no ill effects. That would solve all sterilization problems. Good luck, try making some mead some time.

    Do you have any good recipes? Any sites with them on there??? I was actually thinking about making some for the fall with my roommates!

    I actually tend to just wing it with most of the wine I make. With Mead you need to make sure you add adequate yeast nutrient and that the acidity and specific gravity are ok. There is some variability because honey can be very different depending on region and blending, a mead made from orange blossom honey will have a much different flavor than one made from clover honey. The last batch I made I just added some citrus juice to get the correct acidity but you can choose to manipulate acidity with other juices, or acid blends for winemaking. In addition yeast choice will greatly influence character and flavor of your final product with some yeasts imparting citrus flavors and the natural characteristics of some yeast resulting from lower alcohol tolerance that will influence whether you have a sweet or dry mead. Other considerations include whether or not you want to make a carbonated version and/or whether you want more of a beer style or more of a wine (again, more yeast choices). My advice is to choose a yeast that is hearty and then just have some fun. Make small batches and experiment. That way if you land up with a failed batch it hasn't cost you as much, since the amount of honey used to produce mead can make failures costly (i've made batches as small as 2 liters). Just write down what you do with each batch so if you come up with a combination that you really like, you can replicate it at a later time. In addition if you land up with a batch that doesn't seem to have enough flavor you can do a freezer method concentration, where you freeze what you have then once solid pull it out of the freezer and invert it so you can separate the frozen water from the alcohol and flavor (about an hour of drip time). You'll land up with higher alcohol content and concentrated flavor but will never be able to reach 50% by this method, probably a max around 20% alcohol(this does not count as distillation so don't worry about the legality, so long as you don't make more than 500 gallons per year).
    Here are two possible resources. Have fun!!!

    While extracting alcohol by freezing is not technically distilling, it is still illegal in most states in the US. Here's a quick, small and simple mead recipe (called by the knowing metheglin, which is just a mead with spices and/or fruits added) that you can make in a couple of hours from start to finish (not including fermenting time). If you mess it up, you're not out a lot, since it's only a gallon: 1 Gallon Water 1 Quart clover honey 1 Medium lemon 12 Cloves (about a teaspon) 1 cup breakfast tea Champagne yeast. Boil the water and add the honey; take from the heat and stir well. Add zest and juice of the lemon, the closes and the tea.Let it cool. put into a gallon glas jug and add the yeast. Shake a bit and put an airlock on the bottle. Ferment for two weeks, then bottle. Cap or cork the bottles and let sit at room temperature for two weeks. You can refrigerate then. You can drink it right away, but it will get better with two or three months of rest.

    Sorry I forgot; this is not my recipe. I collected it from the usenet many moons ago when I first got interested, and it's good enough to come do again... and again... :) You can add a stick of cinnamon to it, but I prefer it without. It's great to do with beginners or with friends that don't brew, and since I almost always have some of this around, so when we're done with the washing I give them a bottle to take home - I believe in instant gratification and happy friends. I normally bottle this in brown or green wine bottles with natural corks.

    Thanks! That recipe sounds delicious. I may have to try it. I have just one bottle of my last mead left. I have some blueberry kiwi wine that is ready to be racked and I just bottled up my strawberry wine!

    Damn that sounds like it can get complicated. I bought some wine yeast last year and tried to make some hard cider. I let it ferment for more than a month and it made very little CO2. You could not taste any alcohol in it either... My roommates and I were thinking about making some this year though so maybe we'll try some mead! Thanks for the links!