DIY 5L Mini Keg Carbonator Bung(onator)

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starman

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This project expands principals of the DIY Carbonator Cap to work as a 5L mini keg bung. Since I usually bottle, this also utilizes a 16g cartridge based Cornelius Keg C02 charger for pressurization.

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First off, credit to Richard J. Kinch http://www.truetex.com/carbonation.htm for the original DIY write up. Thanks Yuri for the link.

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Bung Material List: (prices estimated)
5L Mini Keg with gravity spigot and original bung removed. (Not Heinie or Newcastle)
(1) Victor Metal Tubeless Tire Valves ~$5.50 for 2 via Advance Auto Parts
(2) 1" Neoprene washers w/ 3/8" holes ~$0.60 via Ace Hardware
(1) 7/8" Neoprene washer w/3/8" hole ~$0.60 via Ace
(1) 2 1/8" Neoprene washer w/ 3/8" hole ~$2.20 via Ace
(1) 1 1/4" SS washer w/ 7/16" hole
(3) Victor Metal Stem Extensions ~$4.00 for 4 via Advance Auto Parts
1/2" of thin stainless steel wire - free... still keep finding bits of that crap from my batch sparge braid build...
Victor 4 in 1 Valve Stem Tool (Optional)

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This is a pretty straight forward build. Disassemble the Tire Valve and discard all the rubber washers. (Note: Unlike Mr. Kinch's system, you can leave the valve installed) Put the (2) 1" washers on the post first, followed by the 7/8" washer. Temporarily screw on one of the stem extensions to make the next couple steps easier. (Without the extension, I dropped the whole thing in the keg, which was a total PITA to get out.) Push the three washers thru the hole in the keg and snug it up. The 7/8" should fit perfectly flush in the hole. Next, I applied a little KY... er keg lube on the top of the keg and then the last large neoprene washer, followed by the large stainless steel washer. Follow it with the Victor supplied ss small washer and nut. Wrench the nut a bit and violla. Mini Keg, meet Bungonator.

Next we have to modify two of the stem extensions in order to make a filling 'chuck' and an air vent for serving. About 1/8" down from the top of the valve, drill a pair of 1/16" holes opposite each other thru the stem wall. Take care not to go the middle. Next depress the plunger and run the stainless wire through across the top to hold the plunger down. Bend the wire around the outside.

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Screw one extension in the end a 1/4" ID CO2 supply tube and secure with a clamp. You now have a threaded chuck that allows the keg to seal up when you remove from the system. Use the second modified extension to provide a vent tube when serving from the gravity tap.

Cool, crash carb, enjoy! Refill...
 
No issues with denting. The biggest issue I ran into was you still need to let the carbonic acid dissipate for the beer to taste best after a force carb.

I'm not sure about the avanti system personally but I know of at least one micro-keezer project where the guy built manifolds and had several 5l kegs on tap.
 
I know this is an older thread... hopefully someone can help me, Hey folks. ............Thanks for taking the time out to look at my post, I bought the gear to make a small mini keg carb kit with a bike pump inflator and a few odds and ends. I cant quite figure out how to get it attached to the mini keg.

I used the DIY info from this thread and I have included some pictures of what I have done and I would really like to be able to save the beer in the mini keg- its bells wheat ale. I cobbled it together for now- just to keep the beer air tight. but I don't think its air tight. I squeezed some co2 into it and it squished beer out of the top. I cant figure out how to get the lines attached to the keg itself....

I still have the black rubber gasket that came installed on the keg but the red little center fell into the keg/beer

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i Believe it should be assembled as it is laid out in the original posters pic-

schrader
1" washer
1" washer
7/8" washer
lube....
and on the outside of the keg-
big neoprene washer
stainless washer
supplied washer and nut from schrader valve
 
Bingo... Got it! Thank you! You rock! Thanks for the link up to the part... Drinking bells now.. In your honor!
 
I got one of the 2 hole lap stoppers and through one i screwed a bike tube valve and through the other I tightly pulled a 1/4 inch tubing and attached a keg spout to the end of it.

I was afraid of the stopper blasting out with charging the keg, so I simply bought some twine and tied it around the keg to hold the stopper down.

It works great, holds the pressure, and pumps out the brew. It doesn't take much more then a single pump to push out most of the beer.
 
Along those same lines, why not just make a mini keg out of a good 2 gallon water jug? It would be easier to clean and all we would have to do would be attach the hardware to the lid. Or maybe just the valve on the top and change out the spigot to a metal flow valve.
 
I have a question about the CO2 cartridges, does the valve keep in the pressure, or do they eventually leak down if not used? The reason I ask is, I am wanting to force carb my ciders in 1 liter PET bottles, and I have no idea how many grams of CO2 it takes to charge a 1 liter bottle. My plan would be to super chill a bottle of cider, charge it and let it sit overnight in the fridge. I would then remove my shrader valve cap, screw on a regular cap and put the bottle back in the fridge, and repeat. If someone has already done this idea with success, please link me to a post or posts describing their process.
 
What fitting do you need to connect the pipe to the co2 cartridge charger? Also has anyone thought of adding a pressure meter? I am wondering how that would connect in line. I am thinking of building one of these, to be able to not only charge but also monitor the pressure in the mini keg.
 
What fitting do you need to connect the pipe to the co2 cartridge charger? Also has anyone thought of adding a pressure meter? I am wondering how that would connect in line. I am thinking of building one of these, to be able to not only charge but also monitor the pressure in the mini keg.

The co2 charger has a 1/4 ffl (female flare) nut which threads onto the mfi fittings of the usual ball lock Quick Disconnects. The charger I bought (on Amazon) does a decent job of releasing co2 when the trigger is pressed, and it does not leak a lot. BUT - the cartridges are under a lot of pressure and there is no regulation of pressure with it, which can make it dangerous to use in a closed system. I have a carbonation cap I thought I would use with a charger: NOT A GOOD IDEA. Yes, the gauge is a good idea, but you need a regulator. There are some tire inflators that can help you control the release of the CO2; Lezyne comes to mind. I considered the tire chuck/valve scheme, but I don't have any kind of a CO2 system to use with it, so I just bought a mini regulator that can adapt to different CO2 sources. Am just starting to set that up with a cap carbonator on 2 L pop bottles. Keeping fingers crossed. Cheers
 
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