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Can I cut my c02 dip tube to get more beer in the keg?

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JunkCatsOnThePorch

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Ok so I've looked around on here and could only find one person mentioning it once. So Ill ask experienced keggers, as I've been mostly bottle conditioning for a few years.

I have heard that if the beer level hits the c02 dip tube, it will not carbonate.
Last time I kegged, I believe it was at or a notch above the 5 gallon mark.

30psi for 3 days did absolutely nothing to it. I pulled off a pint, hit it with 30 psi for 3 days again and got the desired effect.

Cant I just cut the dang c02 dip tube a bit? or is it long for a reason? Ive got my keg disassembled with a hack saw ready to go and I am debating.

Standard pin lock keg and the tube is 1 1/4 inches long.
 
The 'why' to this question escapes me...there's a lot going on at the top of a keg between head space, the dip tube, bleed-off valve, and the lid seal. I don't see any upside to messing with it.
 
Very true. I have decided not to cut already, started putting it back together.

I bottle condition almost always, now I've built a dandy 3 tap chalkboard keezer and I am learning the ropes.

Although if someone has had a failed/successful experiment with this I would love to hear.
 
Very true. I have decided not to cut already, started putting it back together.

I bottle condition almost always, now I've built a dandy 3 tap chalkboard keezer and I am learning the ropes.

Although if someone has had a failed/successful experiment with this I would love to hear.

You don't really have to cut it to get more beer in the keg. Helps, I suppose,if you have higher pressure in the keg than your regulator is set for, so that you push beer into the dip tube and into you gas lines, but that's pretty easy to avoid. And we're talking a beer or two here. Just control your fermentation volumes a bit more or be willing to lose a little.
 
Really how much more there ain't a lot of room left when its filled right up to it. Go bigger with kegs is a better solution 10 gallon cornys and 15.5 gal sankes.
 
Carbonation time is dependent on surface area of contact. If you fill above the dip tube you will get into the decreasing radius area of the keg and decrease headspace.

I've cut my dip tubes down as I either naturally carb in the keg or use carbing stones.

There really isn't much room above the dip tube though. The main reason for cutting is to help properly purge the kegs of air.
 
I have two dozen 5 gallon pin lock kegs. I have not cut any of the gas tubes only using what came with each keg.

15 of these kegs came with a very short, approximately 1/4" long gas tube. A couple had very long, approximately 2 1/4" long gas tubes. The rest of them have 1 to 1 1/4" tubes.

The short ones might take a bit longer to carbonate but I've never tried to document the difference. I force carbonate all my kegs at my basement's ambient temperature which can range from 53 F to 78 F but is for most of the year about 60 F to 65 F.

So the short answer is yes you can cut them down.

I'm not here to challenge any of the other folks who responded just relating my experience with this issue as you, the OP, requested in post #3.

Of course, YMMV
 
...I have heard that if the beer level hits the c02 dip tube, it will not carbonate.
Last time I kegged, I believe it was at or a notch above the 5 gallon mark.

30psi for 3 days did absolutely nothing to it. I pulled off a pint, hit it with 30 psi for 3 days again and got the desired effect.
I don't see how that could possible be true. You'll still have pressurized CO2 above the beer even if the dip tube is submerged. Although the surface area exposed to CO2 will be somewhat less (maybe half?).

The main reason for cutting is to help properly purge the kegs of air.
I think what Jason is saying (correct me if I'm wrong) is that you need to cut the dip tube down to expel all of the sanitizer, or else you'd leave lots of sanitizer behind when using that purging method of filling with sanitizer then pushing it out with CO2.
 
Yes, when you are filling with sanitizer before purging you have to tilt the keg slightly to the side and let the air that is trapped in the lid (around the PRV) out of the gas in post to get all the air out.
 
Yes, when you are filling with sanitizer before purging you have to tilt the keg slightly to the side and let the air that is trapped in the lid (around the PRV) out of the gas in post to get all the air out.
Thanks for clarifying. So I guess there are 2 reasons: (1) to get the air out when filling with sanitizer, and (b) to get the sanitizer out when pushing in the CO2.
 
Very true. I have decided not to cut already, started putting it back together.

I bottle condition almost always, now I've built a dandy 3 tap chalkboard keezer and I am learning the ropes.

Although if someone has had a failed/successful experiment with this I would love to hear.

I bought a bunch of kegs a little over a yaer ago, and for some reason the CO2 dip tube was like 2 inches longer on one keg than is standard. I cut that bad-boy back with no issues.

I agree with folks that you dont want to get the beer really close to your pressure relief mechanism as that would make a mess, but it's not a big deal to cut the CO2 dip-tube, just dont do it too much!
 
I have 4 ball lock kegs and all the gas side tubes are the same - about 1 1/16" below the o ring. But the post is raised some so the tube only extends into the keg about 1/2 inch. The main thing I have heard is that if the tube is submerged there is a chance that beer will go into the gas lines and possibly into the regulator, gumming things up.

The amount of beer that you would gain is probably no more than one pint.

My pressure relief valves don't extend below the top so I would have to fill the keg so only 1/4 inch was left for beer to get to the PRV.
 
I think what Jason is saying (correct me if I'm wrong) is that you need to cut the dip tube down to expel all of the sanitizer, or else you'd leave lots of sanitizer behind when using that purging method of filling with sanitizer then pushing it out with CO2.

I did something new about this on Monday night when I kegged a couple batches.

I have the receiving keg full of Star-San, and then push that out (using CO2) into another empty keg or, if I'm outta kegs, into the sink. I discovered, dumping into the sink, that I can connect tubing to the "out" side, then as I purge w/ CO2 connected to the "in" side, what little Star San remains in the keg is blown out the "out" side. A little rocking of the keg got it all to the dip tube and out it went. I had no Star-San left in the keg, and never had to open it to let out that last half-cup or so.

This is my new system. Once I've pushed out the Star-San, I'm hooking up tubing to the out side to blow out the remaining Star-San.
 
I put about 1 - 2 cups of Starsan in my keg, put the lid on and swish it around. I wait a few minutes, remove the lid, and pour the Starsan back into the storage container. That way I get to re-use it and it is so much simpler than hooking up co2 to push sanitizer out of the keg. I also get almost all of the sanitizer out this way. My dip tube is about 1/4 inch above the bottom of the keg. So there would be more santizer left there than I would want in my beer.
 
I put about 1 - 2 cups of Starsan in my keg, put the lid on and swish it around. I wait a few minutes, remove the lid, and pour the Starsan back into the storage container. That way I get to re-use it and it is so much simpler than hooking up co2 to push sanitizer out of the keg. I also get almost all of the sanitizer out this way. My dip tube is about 1/4 inch above the bottom of the keg. So there would be more santizer left there than I would want in my beer.

I agree, it's simpler. It also doesn't remove air from the keg, which is my purpose in pushing the Star-San out w/ CO2--that way I have a keg almost 100 percent CO2.
 
I agree, it's simpler. It also doesn't remove air from the keg, which is my purpose in pushing the Star-San out w/ CO2--that way I have a keg almost 100 percent CO2.

Once the keg is empty of starsan and full of co2, just flip the keg upside down and pull the prv. The remaining ounce or two of starsan will blow out. Just residual starsan will be left inside. No biggie.

:mug:


Edit: Won't work with pin locks though, unless there's a prv lid on it.
 
I did something new about this on Monday night when I kegged a couple batches.

I have the receiving keg full of Star-San, and then push that out (using CO2) into another empty keg or, if I'm outta kegs, into the sink. I discovered, dumping into the sink, that I can connect tubing to the "out" side, then as I purge w/ CO2 connected to the "in" side, what little Star San remains in the keg is blown out the "out" side. A little rocking of the keg got it all to the dip tube and out it went. I had no Star-San left in the keg, and never had to open it to let out that last half-cup or so.

This is my new system. Once I've pushed out the Star-San, I'm hooking up tubing to the out side to blow out the remaining Star-San.

I'm missing something ... how were you previously pushing the Star San *without* tubing on the "out" side?
 
Thanks guys. I know the extra pint could be trivial I am just trying to keep things simple. With no waste. And With no beer shooting out, that would be a plus...
 
I put about 1 - 2 cups of Starsan in my keg, put the lid on and swish it around. I wait a few minutes, remove the lid, and pour the Starsan back into the storage container. That way I get to re-use it and it is so much simpler than hooking up co2 to push sanitizer out of the keg. I also get almost all of the sanitizer out this way. My dip tube is about 1/4 inch above the bottom of the keg. So there would be more santizer left there than I would want in my beer.

Yep, got all the sanitizer out but the keg is full of air!!!!
 
View attachment ImageUploadedByHome Brew1475171364.834896.jpg

I did all mine. Aim for 1/2-7/8".

This has several advantages....
-You can get the keg completely full when doing a water purge. Tilt to about 45 degrees while filling through liquid port and venting through gas.
-If you ferment in the keg this gives you another 1/2" or so of head space. That's like another pint.
-Reduced risk of back flow when connecting gas to full keg.

Some other points... the beer will carbonate just fine even if the gas port is submerged. And oxidation is real. It won't make your beer undrinkable, but if you aren't actively controlling oxygen then you have oxidized beer and don't even know it. Oxygen does not ruin beer. It just makes it different. If you like oxidized beer then great, but some of us don't prefer it.
 
Once the keg is empty of starsan and full of co2, just flip the keg upside down and pull the prv. The remaining ounce or two of starsan will blow out. Just residual starsan will be left inside. No biggie.

:mug:


Edit: Won't work with pin locks though, unless there's a prv lid on it.

Doesn't work that well with ball locks either. With the keg upside down, and the PRV open, the lid holds 3 fl oz of liquid (I measured.) If you cut the gas tube short enough, you can tilt the keg so that all residual sanitizer will drain out the gas post..

Brew on :mug:
 
I've never had an oxidation problem so the step is unnecessary for me.
:off::off::tank:

Correction: You've never tasted oxidation so the step is unnecessary for you.

Post fermentation oxidation is very well studied and understood. If you aren't purging O2 before packaging then you are oxidizing your beer.

for example

Ethanol reacts via oxidation to form Aldehydes. Aldehydes above 10ppm can be tasted in light beers and above 35ppm in other styles as a green apple flavor.

Linoleic acid oxidizes into dihydroxy and trihdryxyoctadecenoic acids that are precursors to 2-trans-nonenal. The "cardboard" flavor. This reaction will take some time to develop.

Oxidation will darken the wort color.

Pickup of oxygen during packaging should be less than .03ppm (or as close as you can get) there is no way you can get anything close to this without purging the keg!!! Why go through the whole process then skimp out on spending 2-3 minutes to purge the keg?!?!
 
Doesn't work that well with ball locks either. With the keg upside down, and the PRV open, the lid holds 3 fl oz of liquid (I measured.) If you cut the gas tube short enough, you can tilt the keg so that all residual sanitizer will drain out the gas post..

Brew on :mug:

Obligatory picture :mug::ban:

Volume.JPG


Keg lid.png
 
Once the keg is empty of starsan and full of co2, just flip the keg upside down and pull the prv. The remaining ounce or two of starsan will blow out. Just residual starsan will be left inside. No biggie.

:mug:


Edit: Won't work with pin locks though, unless there's a prv lid on it.

Problem is that there is a cupping on the underside of the lid, and the PRV housing sticks up, what, half an inch? So the Star San just sits inside the cupped part, and doesn't go out the PRV.

I've tried that and it didn't work for me. Maybe I'm not doing it right.

EDITED TO ADD: JDDEVIN's pic above shows the lid very clearly.
 
I'm missing something ... how were you previously pushing the Star San *without* tubing on the "out" side?

I should have been more clear. Typically I use a jumper with a liquid QD on both ends that draws from the one keg and fills the other via the OUT post.

Monday I had no empty keg into which I could transfer the Star-San to save it, so into the sink it went. But the jumper has the QDs on both ends, which won't work. So I use the line that has a liquid QD on one end, and no QD on the other.

This is the line I use to fill the keg from the fermenter, so the beer enters into the OUT post and fills from the bottom up, into a keg that is virtually full of CO2 and not air.
 
Problem is that there is a cupping on the underside of the lid, and the PRV housing sticks up, what, half an inch? So the Star San just sits inside the cupped part, and doesn't go out the PRV.

I've tried that and it didn't work for me. Maybe I'm not doing it right.

EDITED TO ADD: JDDEVIN's pic above shows the lid very clearly.

That's why we are cutting the tube :fro:

  • After you've pushed out all the sanitizer you can upright
  • lean the keg so that the gas in post is the lowest part
  • Hook a QD or poke it with a screwdriver and the rest of the sanitizer that was sitting at the lowest part (by the cut tube) will shoot out

Can't do it without cutting the tube :tank:



I fill my kegs from the fermenter by "jumpering" the in post of the first keg to the following keg out post so that after the first is full the second starts filling.... since I want them full the cut tube helps with that
 
Problem is that there is a cupping on the underside of the lid, and the PRV housing sticks up, what, half an inch? So the Star San just sits inside the cupped part, and doesn't go out the PRV.

I've tried that and it didn't work for me. Maybe I'm not doing it right.

EDITED TO ADD: JDDEVIN's pic above shows the lid very clearly.

Oh yeah, that is correct. All the newer lids are like that. Most of my lids are the old Firestone type, and the prv is flat to the inside of the lid. Easy to drain.

I do have some newer lids, and my theory will not work for those types. Sometimes I get a bit of tunnel vision, and forget about stuff. Lol!


Not too big of a deal though. I've drank diluted starsan before. Tastes like lemonade... but without sugar... or a lemon taste. Lol! If that makes any sense. I don't really recommend it though, but it shouldn't cause any off flavors in beer if minimal amounts, or at least I never noticed.

:mug:
 
Looking inside a corny keg there is a black line about an inch below the top of the keg. That line is where the keg wall is welded to the keg top. That is where corny kegs are 'recommended' to filled up to.

Sometimes I force carbonate a full keg of beer by connecting the gas line to the beer out post and never had any issues getting great carbonation.
 
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