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!



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    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

    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...

    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.