Will the real Carboy Please Stand Up

[asterof]

so in my constant state of confusion, I need some clarification on the real measurement of a Carboy.
Lets take for instance that a kit that makes six gallons.
So you go through the primary, secondary, filtering and want to go to
aging in the Carboy. Why then is it that a six gallon kit, and yes it made six gallons, never fills a six gallon Carboy to the neck.
I think it is a conspiracy to make you mess up and go buy a smaller one each time.
Now in years past we measured an ounce with three fingers.... oh wait wrong subject, we were discussing Carboys.
So what say ye on where is a Carboy actually measured.
Thanks

 

[ckvchestnut]

Do you not lose volume on racking? At my first rack I lose volume due to lees. Then I lose even more after clearing... Is that what you are referring to? Also it's probably a good idea to ensure that your primary fermenter is marked with the gallon levels just in case your juice doesn't measure up exactly...

 

[grapeman]

Many of the newer Italian made carboys are actually close to 6.5 gallons. The old Mexican made ones were much closer to 6 gallons.

 

[ckvchestnut]

Really? How the heck can they advertise them as such then? I have both types... I'm going to have tondo some measurements for fun. Thanks for info Grapeman

 

[ckvchestnut]

I probably would have figured that out earlier but I do batches from scratch and always make a gallon extra for topping off. Now that i'm doing a few kits here and there I'm noticing a slight difference.

 

[sour_grapes]

Yes, the carboys are all different sizes.

Here is what people were kind enough to tell me when I ran into the same quandary:
http://www.winemakingtalk.com/forum/f3/carboy-confusion-41520/

 

[Turock]

This is the inside joke around OUR winery----Some of these manufacturers don't seem to know what 5 gallons IS. We find lots of variation with all the 5 gallon carboys, especially!! The antique ones made in the USA hold more than any of the foreign made. Our cure for this is to have lots of marbles available.

 

[ckvchestnut]

Wow thanks so much for the link and the responses! I found that really helpful! I'm going to measure all of mine and try to rack down to whichever ones are smaller if I have any. I think I have a few smooth ones, 3 ribbed ones and 1 plastic one in 6 gal. 3 - 3gal with ribs. I'll see about those too.

 

[Boatboy24]

Yep, definitely close to a half gallon of extra capacity on those Italian carboys. I think the 6 gallon mark is right at the shoulder.

Better Bottle carboys seem to be pretty much right on 6 gallons though.

 

[ckvchestnut]

Wow I still can't get over this! Can't wait to measure mine. I'll measure 6 gals into one of my smooth ones and then syphon that into my other ones and mark them each at the 6 gal level. I'm having a revelation now from some times when my levels only went to the shoulders! But usually I make extra so I never noticed that problem.

 

[DoctorCAD]

4 fingers, by the way...

Carboys are grossly made and not subject to any real standards. I have 4 5 gallon Better Bottles and they are all very close, but I also have 2 glass 6 gallon carboys that are not even close.

My suggestion is not to worry about it and use whatever volume you need to fill the carboy.

 

[ckvchestnut]

Ya that's fine and what I've been doing but I just hate the thought of diluting kit wines or juice buckets to fill up carboy space. What's the typical amount of marbles needed to fill from the shoulder to the neck? Anyone know? I'm going to look at how I can make a PVC tube that with removable capped ends to place the marbles on so they are easy to remove. What I'm picturing is two tubes one that fits inside the other. Both with tiny holes drilled in at the same places. So if you want to use the tube to implement oak chips you slide the tubes so the holes are matching up and in the open position so the oak can do its job. When you want to displace the volume, you can use the tube to fill with marbles and you keep the holes closed. However finding 2 tubes that fit tightly and water tight might be too much of a challenge. So maybe have 2 on hand, one for oaking and the other for displacement.

 

[BernardSmith]

Slightly off topic but not really because we are measuring volume and volume is subject to change with temperature. Does anyone know how large or small a US gallon actually is when it comes to buying gas for your car? A gallon of gas in December when the outside temperature is 32 F must be considerably smaller than a gallon bought in July when the outside temperature is 95 F. What temperature is gas stored at? And how often is this volume modified to allow for variations in temperature? Does James in TX pay for a smaller gallon than we get in NY?

 

[grapeman]

Bernard a gallon is a gallon is a gallon. Since it is a measure of volume, the volume remains the same, it is only the liquid within it that changes. The container size does not change, only what is within it. A more accurate measure would be by weight, which does not change but would be very cumbersome because the weight of a gallon (or any other measure) varies from item to item. A gallon of wine weighs a bit different than a gallon of gas or water. For practical purposes it is accurate enough for most uses.

 

[sour_grapes]

Grapeman is correct. Moreover, gasoline has a fairly hefty coefficient of thermal expansion, so the effect is non-negligible.

As a result of your question, I just learned that gasoline sold at wholesale is compensated for the temperature, but not at retail.

 

[ckvchestnut]

Ummm I get messages at my pump that say corrected volume and some temp degree what does that mean?

It appears to me that everyone must hold their gas at a standard temp in the tanks.

 

[RegionRat]

Slightly off topic but not really because we are measuring volume and volume is subject to change with temperature. Does anyone know how large or small a US gallon actually is when it comes to buying gas for your car? A gallon of gas in December when the outside temperature is 32 F must be considerably smaller than a gallon bought in July when the outside temperature is 95 F. What temperature is gas stored at? And how often is this volume modified to allow for variations in temperature? Does James in TX pay for a smaller gallon than we get in NY?

One US gallon is 231 cubic inches. That is what I was taught many years ago in fire school. As for temp I would guess it would be at 60deg f.

This is just a guess when it come to weight. I would think the standard for one US gallon would be 128 fluid oz of water at 60 deg f.


Edit*

From Wikipeda:
The US gallon, which is equal to 3.785411784 litres, is legally defined as 231 cubic inches.[1][2] A US liquid gallon of water weighs about 8.34 pounds or 3.78 kilograms at 62 °F (17 °C), making it about 16.6% lighter than the imperial gallon. There are four quarts in a gallon, two pints in a quart and 16 fluid ounces in a US pint, which makes a US gallon equal to 128 fl. oz. In order to overcome the effects of expansion and contraction with temperature when using a gallon to specify a quantity of material for purposes of trade, it is common to define the temperature at which the material will occupy the specified volume. For example, the volume of petroleum products[3] and alcoholic beverages[4] are both referenced to 60 °F (16 °C) in government regulations.


Ummmm, and yes it used to be 4-fingers
RR

 

[SmokeyMcBong]

i like your guys ounces!!

 

[Runningwolf]

It appears to me that everyone must hold their gas at a standard temp in the tanks.

Sometimes that's easier said than done. Sorry I couldn't help it.

 

[Runningwolf]

Ok a bit off topic but a long the same line. This just happened to me this week. An elderly couple came in last week to buy 21 gallons of wine. I had it ready for them ahead of time. Well they called this week and said I ripped them off by two gallons. When they got home they filled up their one gallon jugs and were short by two gallons. Well I knew I was generous on what I gave them and it bothered me all day. Finally I looked up how many ml's were in a gallon and filled one up with water. Guess what? There was still a good bit of head space. I forget how much but it was well over 100 ml.

The bottom line was, if they filled every jug to the very top (which they should have) they would be nearly 2 gallons short.