Keg Volume

On Thu, 23 Sep 2004, Lew Bryson vociferated:

}Get a goddamned scale and weigh it, and stop ruining my sleep!

Done.

In fact, I did it years ago.

Dr H

On Thu, 23 Sep 2004, Bob vociferated:

}On Tue, 21 Sep 2004 19:56:24 -0700, "Steve Jackson" } wrote: } }>Only if it's American. And that's water. Technically speaking, beer with its }>dissolved solids, will weight slightly more. Not enough to make any }>appreciable difference in a pint, of course. } }But what about a keg's worth - 15.5 gallons?

Little over 129 lbs of beer plus about 14# for the typical cylindrical keg.

Dr H

I can't do the calculation because I do not know the specific gravity of a typical beer.

My son and I are the only ones drinking from that keg and we are not boozers - although we have been known to drink a bit above the average on occasion.

So weighing is meaningless unless you know the specific gravity.

For example if you took 8.5 as the density of BudMiller swill, and it turned out to be 8.33 as suggested above, then the error would be 2% or 1/3 of a gallon.

Unfortunately I threw out my float hydrometer from the days of home brewing, or I could measure it on an individual basis. I suppose I could always get another.

I thought of that but the CO2 would leak out before I could plug the holes.

There is an expensive device on the market that you attach to the faucet handle and it keeps track of how many times you open the faucet. You calibrate it by inputting the volume of a keg after running it empty. The problem with this is that you must pour the same volume every time. If you flick the handle to cut back on foam near the end, you have screwed the calculation.

I can get a rough idea by lifting the keg. I want something better than a rough idea. An ultrasonic depth transducer would work but that is an expensive device for something so simple as measuring beer level.

I tried using a stethoscope and tapping on the side of the keg, listening at various levels for a change in the sound. But I was unable to discern any change.

There's got to be a cheap solution to this problem. I and a lot of other keg beer owners would pay $20 for such a device that gave an accurate measurement.

I can do the math just fine. I just don't feel the need to do it for people who are too lazy to do some pretty basic arithmetic themselves.

-Steve

Then you are too lazy to be on this forum.

I'm too lazy because I won't do simple math for you?

Apparently your vocabulary is just as sharp as your math skills.

-Steve

Yes, you are.

Apparently you are wrong.

In order to calculate the density of beer one needs to know the specific gravity. I do not know the typical SG of beer (I used to when I made homebrew, but that's a long time ago).

But never mind - don't trouble your math-challenged brain one bit. A kind poster - one from whom you should take lessons on how to be helpful instead of a snotass - told us that beer typically weighs between 8 1/3 - 8 2/3 lb per gallon, with swill like BudMiller coming on around 8.33.

I'm really baffled at how *I'm* lazy because I won't do your homework for you. Whatever.

Most average-strength beers end up with a finish gravity in the 1010 to 1015 range. You probably could have found that in about 60 seconds on Google.

From there, figuring the weight per gallon is stunningly easy, as well as multiplying it by the number of gallons in a keg.

Not doing your research for you is not being a snotass. Expecting others to do it for you is. HTH.

-Steve

In other words, a poster totally unlike yourself. Go away, you asshole. You're a waste of air and bandwidth.

On Fri, 24 Sep 2004, Bob vociferated:

}On Fri, 24 Sep 2004 13:52:14 -0700, Dr H wrote: } }> 9 days? Hell, when I have a kegger we go through it in 2-3 days. } }My son and I are the only ones drinking from that keg and we are not }boozers - although we have been known to drink a bit above the average }on occasion. } }>}What is the weight per volume for beer? Water is 8 lb / gal, so I }>}assume beer is close to that. I am going to weigh the next keg I get. } }> Beer is ~8-1/3 to 8-2/3 lbs. per US gallon, depending on what kind you've }> got. } }So weighing is meaningless unless you know the specific gravity. } }For example if you took 8.5 as the density of BudMiller swill, and it }turned out to be 8.33 as suggested above, then the error would be 2% }or 1/3 of a gallon. } }Unfortunately I threw out my float hydrometer from the days of home }brewing, or I could measure it on an individual basis. I suppose I }could always get another.

Actually the difference between a typical low gravity brew and a typical high gravity brew isn't that much -- maybe 4-6% -- which only makes a difference of five pounds or so in a 1/2 keg.

Anyway, Bud is at the low end of the scale -- about 8.33 lbs/gallon. If you're pumping a pale ale or an IPA you /might/ be up around 8.4 lbs./gallon. Maybe.

}> You could drill a small hole in the side of the keg and keep drilling }> lower and lower until you hit brew. ;-) } }I thought of that but the CO2 would leak out before I could plug the }holes. } }> Or you could use a standard size glass/cup, say 16 oz., and have a }> tick-off sheet that people make their mark on everytime they draw a }> brew. Drunk people tend to forget to tick-of every time, but you'll }> still get a rough idea of how much beer is left. } }There is an expensive device on the market that you attach to the }faucet handle and it keeps track of how many times you open the }faucet. You calibrate it by inputting the volume of a keg after }running it empty. The problem with this is that you must pour the same }volume every time. If you flick the handle to cut back on foam near }the end, you have screwed the calculation.

Hell, depending on what it costs it might be cheaper to just get a flow meter and put it in-line with the tap. If you're really into the gagetry...

}I can get a rough idea by lifting the keg. I want something better }than a rough idea. An ultrasonic depth transducer would work but that }is an expensive device for something so simple as measuring beer }level. } }I tried using a stethoscope and tapping on the side of the keg, }listening at various levels for a change in the sound. But I was }unable to discern any change. } }There's got to be a cheap solution to this problem. I and a lot of }other keg beer owners would pay $20 for such a device that gave an }accurate measurement.

If you want cheap, and you don't need multi-decimal place accuracy, buy a bathroom scale and rig up a cheap plywood platform to set the keg on it. Tare the scale to zero with the plywood and an empty keg on it, then set the full keg on, watch the weight decrease, and do the math. If you start with 130 lbs of beer, when you're down to 117 pounds you've used up 10% of the beer; etc.

Dr H

I thought of doing that - I even have the scale in mind, a digital one. However, they are not cheap and my wife would fuss if I took her scale for something as mundane as measuring the weight of a beer keg in situ.

Plus there is the matter of how temperature affects a scale. I do not know if 38F temp would mess it up. If I were ever to rig something with a scale I would probably try one of the el cheapo spring-based models. But then who knows what results I would get.

Then there's the matter of space - as it is now the refrigerature I am using has a bulge in the back on the floor which means I have to set the keg on the bottom shelf that holds the vegetable bins. I had to use a right-angle connector on the beer line from the tap to prevent it from hitting the freezer bottom. I have about 1/2" clearance as it is, so rigging a scale would not be possible unless I built an elaborate platform to sit on the bottom and clear that bulge.

My son, the one with all the experience in home beer kegs setups from his college days, just reaches into the refrigerator, lifts the keg and pronounces his estimate - like "we still have beer". That's worked thus far, but since this is our first keg he has yet to prove his skills with an actual empty keg.

I am beginning to believe that I can tell the level by tapping the keg

- it gets more like a deep hollow sound each day. I suppose I will have to do like others and keep a case of bottled beer ready for the day we have to swap out the keg. Hopefully it won't run out on a Sunday because that will entail a 2 day turnaround.

With as many people into home keg setups, you would think some enterprising engineer would devise an inexpensive method - possible based on sound. One day I am going to dismantle that electronic stud finder to see if there is a transducer available that will work reliably.

You know the old saying - "If we can put a man on the Moon, we should be able to measure the level of beer in a keg."

Slow poke! ;-)

Yeah, but this is Shiner Bock, not to be confused with BudMiller swill. You sip this stuff, not gulp it.

Zeigenbock tastes about the same and is $22 cheaper per keg.

On Tue, 28 Sep 2004, Bob vociferated:

}On Tue, 28 Sep 2004 13:07:13 -0700, Dr H wrote: } }> If you want cheap, and you don't need multi-decimal place accuracy, }> buy a bathroom scale and rig up a cheap plywood platform to set the }> keg on it. Tare the scale to zero with the plywood and an empty keg }> on it, then set the full keg on, watch the weight decrease, and do }> the math. If you start with 130 lbs of beer, when you're down to }> 117 pounds you've used up 10% of the beer; etc. } }I thought of doing that - I even have the scale in mind, a digital }one. However, they are not cheap and my wife would fuss if I took her }scale for something as mundane as measuring the weight of a beer keg }in situ.

How cheap do you want? The last bathroom scale I bought cost under $20. Digital readout, and all. Try JC Pennys.

}Plus there is the matter of how temperature affects a scale. I do not }know if 38F temp would mess it up. If I were ever to rig something }with a scale I would probably try one of the el cheapo spring-based }models. But then who knows what results I would get.

Temperatures within the typical range of human habitations -- say -30F to +120F are not going to appreciably affect a bathroom scale. Hell, you're only going to be able to read it to the nearest full pound, anyway.

}Then there's the matter of space - as it is now the refrigerature I am }using has a bulge in the back on the floor which means I have to set }the keg on the bottom shelf that holds the vegetable bins. I had to }use a right-angle connector on the beer line from the tap to prevent }it from hitting the freezer bottom. I have about 1/2" clearance as it }is, so rigging a scale would not be possible unless I built an }elaborate platform to sit on the bottom and clear that bulge.

Yeah, that's the bulge where the compressor &etc. sits. Annoying when you want to use the fridge for kegs, and trust me, I know. Still, it wasn't all that much work fabricating a simple plywood shelf to hold the keg and clear the bulge. There are also old friges out there with flat bottoms...

}My son, the one with all the experience in home beer kegs setups from }his college days, just reaches into the refrigerator, lifts the keg }and pronounces his estimate - like "we still have beer". That's worked }thus far, but since this is our first keg he has yet to prove his }skills with an actual empty keg. } }I am beginning to believe that I can tell the level by tapping the keg }- it gets more like a deep hollow sound each day. I suppose I will }have to do like others and keep a case of bottled beer ready for the }day we have to swap out the keg. Hopefully it won't run out on a }Sunday because that will entail a 2 day turnaround. } }With as many people into home keg setups, you would think some }enterprising engineer would devise an inexpensive method - possible }based on sound. One day I am going to dismantle that electronic stud }finder to see if there is a transducer available that will work }reliably. } }You know the old saying - "If we can put a man on the Moon, we should }be able to measure the level of beer in a keg."

For that kind of gear you might want to try a post to one of the brewing newsgroups -- rec.crafts.brewing, or alt.homebrewing. This is more of a generic beer forum, whereas hombrewers tend to be a lot more into the gadgets. I know, because I are one meself, but my solution to a keg running out is to just have an extra keg handy at all times.

;-)

Dr H

The last one we bought was $40.

Plus there is undoubtedly a non-trivial variation in empty keg weight.

I might do that some day, but for now we are able to muscle the keg onto that plastic shelf. Amazingly it is strong enough to carry the weight of a full keg - especially if you position the keg in the rear corner. However, we broke the light so be careful positioning the keg.

Our first keg ran out last night. It was not very ceremonious either - one minute I was drawing beer and the next I was drawing foam. When that sucker goes empty, it goes empty with a vengeance.

I decided I was not going to drill a hole in our brand-new refrigerator so I am using a picnic faucet. The hose is long enough so that I can reach in, grab the faucet from a hook I made for the top of the keg, pull it out and shut the door 90% of the way while I draw beer. Each time I do that I rap the side of the keg with my knuckle to hear the response. I have been doing that enough that I could swear I can tell the difference between where there is beer and where it is not.

The last couple days I noticed that the sound acted as if the keg was going empty. Last night about 4 pints before it emptied, I could not find any place where it sounded like there was beer behind the wall. I suspect that was because the remaining 1/2 gallon was down in the concave part of the keg.

If this is true and I am not just kidding myself, then I may have come up with a way to determine beer level. In particular, once I am unable to find the sound that comes from beer being present behind the keg wall, then I would know that I have about 4 pints left. That would be ideal.

Has anyone trained their ear to determine beer level from rapping the keg in various places with their knuckle or something else? I found the knuckle to be the best for this purpose. A metal object makes too loud a sound and I cannot discern any difference even when I know where the level should be.

On Fri, 1 Oct 2004, Bob vociferated:

}On Thu, 30 Sep 2004 15:05:23 -0700, Dr H wrote: } }> How cheap do you want? The last bathroom scale I bought cost under $20. }> Digital readout, and all. Try JC Pennys. } }The last one we bought was $40. } }> Temperatures within the typical range of human habitations -- say -30F }> to +120F are not going to appreciably affect a bathroom scale. Hell, }> you're only going to be able to read it to the nearest full pound, }> anyway. } }Plus there is undoubtedly a non-trivial variation in empty keg weight.

Empty kegs weigh between 15-20 lbs, typically. Considering that you're dealing with 130-140 lbs of beer, you're only going to be off by maybe 3-5% even if you mis-estimate the empty keg weight. Why would you need more accuracy than that? When you get down to 20% it's time to buy more, anyway.

If you want cheap, easy, *and* high accuracy/precission, you're probably SOL, unless you invent something yourself, and distribute it for free as an altruistic gesture to the beer drinkers of the world.

[...] } }Has anyone trained their ear to determine beer level from rapping the }keg in various places with their knuckle or something else? I found }the knuckle to be the best for this purpose. A metal object makes too }loud a sound and I cannot discern any difference even when I know }where the level should be.

Get yourself one of those little rubber mallets doctors use for testing knee reflexes -- might save you some bruised knuckles.

Dr H

Where am I going to keep the second keg until I empty the first one?

Accuracy rules out the weight method. It has to be a direct level measurement, and that means ultrasound. Now the question is whether there is an inexpensive ultrasound transducer on the market that will yield reasonable accuracy.

The only method I know to keep beer available from one keg to the other is to keep a couple six packs of bottled beer in the refrigerator.

I have tried several items, including something similar to what you describe. The knuckle makes the best rapping device. You do not need to rap the keg hard to get it to resonate. In fact the lighter the rap the better the difference in sound.

Maybe the keg-making industry would put an inexpensive electrical/electronic low-beer probe in each keg to determine when you are almost empty. Call it the Smart Keg (TM).

I still want to experiment with a hair drier to see if the frost line reveals the level. The idea would be to heat a vertical strip along keg and let it cool with humidity present. Perhaps it would create a distinctive frost line.

Eh? Shiner Bock isn't particularly thick or strong. It's pretty damn easy to gulp, actually, as it's a fairly refreshing drop. And while it's fine on its own merits, the brewers at Spoetzl don't completely shy away from using adjuncts in that beer. It's a good everyday beer, but needs no place on a pedestal.

Ziegenbock tastes of A-B's house acetaldehyde-spewing lager yeast, which is unsurprising. They deliberately price it lower than Shiner Bock to undercut it; A-B makes no secret that it intends Ziegenbock to be a Shiner-Bock-killer in its home market, and doesn't sell the stuff outside of Texas. At least not yet.