How to biuld a home CO2 carbonation system (the nozzle part)

There's really no reason to go anywhere near 150 psi. 50 psi is more than you'll ever need unless your just in a panic of a hurry. And there's no danger in agitating it as long as you are not hitting the bottle with a sharp object. Just shake the bottle. Even just shake the top back and forth to make crashing waves, which increases surface area and CO2 absorbtion. Shaking the bottle decreases the pressure, as the CO2 disolves into the water. It does not increase the pressure because the pressure at the top is higher than the stabile pressure in the CO2 in solution.

You could make a filler cap with a 5 micron air stone that reaches to the bottom of the bottle. Or, you can shake the bottle, or just be more patient.

Hmmm... That might be interesting.

I did understand your point. What you're saying is that a blind taste test might not know the difference if we either (a) Mix 1/2 seltzer + 1/2 water, or, (b) Mix 1/2 seltzer + 1/2 juice.

The pro is that this is as simple as it gets ... Of course, the obvious con might be that test (a) isn't bubbly enough and test (b) is too diluted (in addition to potentially not being bubbly enough).

But it's worth a try from someone out there.

BTW, I saw articles suggesting dropping a chunk of dry ice into the liquid (outside, in case it pops the top when the very cold dry ice fizzes into the not as cold liquid). That would accomplish the same thing as you are suggesting.

I keep a "corney keg" of water (5 gal soda keg) full of water and carbonated, with a tap. I often just put a spoonful of flavoring, like "coffee syrup flavors" into a glass and top it off with the soda water.

bottom

That's another interesting idea!

Looking up air stones, I find such a thing exists (aka diffusion stone):

Right now, I have August Schrader's valve (.305" OD, 32 tpi or 7.7 mm OD,

32 threads per inch), which was chosen for ease of installation (5/16th inch hole) and sealability (rubber gaskets & tie-down nut).

We could put a similar threaded pipe sticking halfway on each side of the soda cap. On the bottom half (the half that goes into the bottle), we could put a hose and the 5 µm "air stone".

I would assume the air stone should be large in relation to the bottom of the bottle so as to get as great a surface area as possible to bubble up since the pressure will soon equilibrate, hence the bubbling would (I guess) stop in seconds.

Of course, the partial pressure of C02 is what matters so, even though the bubbling that pressurizes the 1 liter soda bottle stops, the inside of the bottle will be pressurized to 50 psi.

This diffusion stone idea just might work.

Very astute observation!

I love the healthy exchange of ideas!

This guy carbonates in GLASS bottles (using a 2 micron carbonation stone)!

By the way, the air-chuck idea promoted in some of these articles doesn't work as well as connections that are constantly open to the carbon dioxide.

Also, a quick call to the 800 Coca-Cola number confirms the 2-liter Coke bottles are tested at 200 psi (amazing that they get this question often).

WARNING: California outlawed many brass fittings as of January 1, 2010, so those of you in the tax state may have trouble buying lead-free fittings on line (most non-California brass fittings have up to 2% lead for ease of machining).

This guy's chart shows the Co2 you can put in liquids based on temperature:

He says at 30°F, you only need 10 PSI to carbonate soda to 3 parts Co2 per volume, while at 45°F you have to bring the pressure up to 25 PSI to get the same result, up to 60°F where you need over 30 PSI to get 3 parts of Co2 per volume of liquid.

There's a picture of the guys pump system carbonator here

I think I'll just stick to a CO2 tank and regulator.

Myself - I wouldn't bother. I've read a lot about this kind of thing for corney kegs, but find for myself that just applying pressure and shaking them does the job just fine. Other times, I just turn on the high pressure every time I wander by the keg for a few seconds, until I get the pressure I want. You could do either with your bottles and It will work fine too. The more open space at the top of the bottle, the less times you will need to repeat the CO2 addition for the desired result.

-- Cheers, WB .............

Indeed! That Richard J. Kinch treatise, titled " Carbonating at Home with Improvised Equipment" was what gave me the idea to build my own carbonator. He delved into the SCIENCE of it all; which gave me courage!

But even that wonderful tutorial missed out on a few points. For example, "infusion" and not "flow" are what he should have used to describe how you get 4 liters of CO2 into a 1 liter bottle of Orange Juice in a closed system.

Also, he didn't describe some technical points, some of which are listed in this CO2 Dynamics web site

such as a "full" tank contains only about 34% liquid CO2.

But most surprising (to me), was the statement that the pressure of a co2 tank has nothing to do with the amount of co2 in the tank; the pressure (as long as there is "some" liquid in it) is always dependent solely upon the temperature.

"At room temperature (70°F) it's about 853 psi."

So, with my new carbon dioxide tank, I'm not sure how I tell how much co2 is left in the tank. Does anyone know how you tell when it's getting low?

Given a co2 tank at 72°F has a pressure of 860 psi (as long as there is some liquid still in the tank) according to this nice C02 tank care article:

I'm curious ... Q1: How do you know when you're "almost out" of liquid in a C02 tank???

Shake it, dont stir. (according to J.B.)

I'm learning more and more how to build (and maintain for safety) a home carbonating system!

Since C02 pressure is around 800 psi, I was wondering why my C02 gauge goes muuuch higher. I found out the Co2 pressure is logarithmically temperature related ... so at reasonably warm summer temperatures (over 90°F), the C02 tank pressure could climb over 1200psi!

So, the first thing is to keep the tank covered from sunlight!

Also keep the C02 tank vertical! This article explains why.

BTW, some people use C02 tanks to fill large off-road tires because a typical air tank (they say) doesn't hold enough air. Interesting:

Yes. I'm trying to learn as much as I can about the proper assembling & use of a home carbon dioxide soda fountain.

Another thing I learned is that I should NOT have used that Teflon tape to seal all the joints in the regulators and hoses! :()

According to this article

Teflon "flows" and refuses to "wet" but it "shreds", thereby fouling the regulators.

So far, I think I've made every mistake you can make! :(

- I had the C02 bottle on its side

- I pressurized the soda bottle to 150psi

- I used Teflon tape to seal the high-pressure fittings

- I used a tire chuck with an intact Schrader valve (instead of removing the stem of the Schrader valve) etc.

But, I'm learning ... Any advice you can give is always welcome!

With a little personal experience, you can tell by the weight of the tank.

And once the liquid is completely gone and the pressure starts dropping, you probably have a few days of usefulness remaining. A few liters of CO2 at 800 PSI is enough to carbonate 10's of liters of soda before the pressure in the tank drops to the 100-120 PSI or so used for carbonation.

- Don Klipstein ( snipped-for-privacy@misty.com)

Ummm... arithmetic? Weigh the empty tank (or ask the supplier for the empty weight). Weigh the tank with whatever amount of C02 you have left. The difference is how many pounds of C02 you have left.

You can also sorta do it the same way as with a propane tank. Get a liquid crystal thermometer strip and glue it vertically to the side of the tank. Leak a little gas and you should see the warm/cold liquid dividing line. The problem is that the propane tank is quite thin compared to most CO2 tanks, thus making the thicker CO2 tank more difficult to see the dividing line. It also works best with steel tanks, and doesn't work at all with aluminum.

You can also use an IR thermometer to locate the liquid level.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com               jeffl@cruzio.com
# http://www.LearnByDestroying.com               AE6KS

Weigh it, perhaps?