Primary Bucket Volume Measurements

[homebrewer_99]

OK, it's Sunday and I got bored...

Long story short, I added water (using a 1/2 g measuring cup) and poured it into my buckets to verify volume levels pre-printed on the pails.

These NEW lines WILL BE transferred to my pails. Repeating this process for your pails may be something to think about.

Here are the results: Lines on tape are the measurements I got.

Pail 1: Frosting bucket from WalMart bakery.
Pail 2: Brewersbestkit pail.
Pail 3: Generic "Ail Pail".

 

[Carolina_Matt]

Holy crap, the one on the right is way off. I just assumed they were close.

 

[homebrewer_99]

Sadly, me too...

 

[bob1852]

Holy crap, the one on the right is way off. I just assumed they were close.

What if it's the 1/2 gallon measuring cup that's wrong?

 

[Vale71]

What if it's the 1/2 gallon measuring cup that's wrong?

Luckily all it takes to check for that is a scale.

 

[Robert65]

^^^^
Exactly.

When making a dipstick or otherwise calibrating vessels, I would never use a volumetric measuring device to transfer measurements, that is, trust someone else's marks on a pitcher or bucket. That's exactly the problem you started with. I weigh my increments of water and then mark where they come up to. One gallon of room temperature water weighs 8.34 pounds, or even more precisely, 3785 grams. If you have a good scale for weighing your grains, use it to calibrate kettles, fermentors, etc.


[EDIT To make sure we're on the same page, I'm referring to US gallons.]

 

[Vale71]

That's actually 3778.7 grams. Don't forget one of several anomalies of water.

 

[Robert65]

????

So *possibly* as low as 3780 depending on your definition of room temperature, but water will never weigh anywhere close to your figure.

 

[Vale71]

I was going with 20°C. My (Windows) calculator says 3785.41X0.99823=3778.7098243

Crap, I see now where a typo slipped in. Fixed it.

 

[Robert65]

And the upshot is, if you just take 3785g as a gallon of water, across the wide range of temperatures we might expect of tap water from place to place and season to season: in the worst case, over 5 gallons, you'll still be off by around a tablespoon, which is a heck of a lot better than those buckets!

 

[Spartan1979]

When I did that I used a one gallon water jug. I filled it by weight and marked the volume. I filled the rest of the gallons by volume.

 

[Deadalus]

Luckily all it takes to check for that is a scale.

What if the scale is off.

 

[ncbrewer]

What if the scale is off.

+1
I would use a volumetric flask if I wanted to be accurate. This could be used to calibrate the scale. So far, I haven't seen the need to go that far.

 

[Robert65]

+1
I would use a volumetric flask if I wanted to be accurate. This could be used to calibrate the scale. So far, I haven't seen the need to go that far.

IME flasks are only vaguely approximate, as per their disclaimers. Scales are easy to calibrate. All you need is a reference weight. But we can more safely assume that the factory calibration of a scale is accurate. Unlike flasks, pitchers, and pails, they are intended to be used as precision measuring tools.
View media item 70841

 

[Deadalus]

A scale might be better than a graduated cylinder (or not) depends on the accuracy of the device doing the measuring. That's what you need to know before judging. Maybe most scales are better than measuring cups, flasks, beakers etc. but its not guaranteed.

The other thing is, if you are just measuring gallons, perhaps how far off the volume measurement device is compared to the scale is unimportant. For instance off by a few fluid ounces vs grams.

Definitely reasonable to check the buckets though.

 

[Vale71]

What if the scale is off.

https://www.amazon.com/s?k=reference+weights&ref=nb_sb_noss_1

 

[Deadalus]

https://www.amazon.com/s?k=reference+weights&ref=nb_sb_noss_1

So many to choose from, there's one for $3.99, one for $18.99, and one for $149.99? What if the reference...oh nevermind!


(I don't want to know why the colon cleanse shows up in that link!)

 

[ncbrewer]

IME flasks are only vaguely approximate, as per their disclaimers.

Volumetric flasks are pretty accurate. This one https://www.amazon.com/Volumetric-G...hvlocphy=&hvtargid=pla-4583863980029287&psc=1 is a 500 ml volumetric flask with a tolerance of +/- 0.25 ml. I agree you can calibrate a scale and figure in the density, but straight volume seems simpler to me. It's a shame that some buckets are so inaccurate - doesn't seem like it would cost much to have the volume marks reasonably accurate.

 

[bracconiere]

i'm just here to find out what picture won't show up? lol but got a laugh out of worring about a 1/4" on a bucket......

 

[Baglorious]

Also, when you purchase your volumetric flasks... make sure your table is level.

And before someone else says it, make sure your level is, um... level.

 

[day_trippr]

Test

 

[ba-brewer]

looks approximate to me

 

[day_trippr]

lol - sorry, I re-posted that image (seen earlier) to see if we could figure out a mystery with the Tapatalk app...

Cheers!

 

[Nanuk-O-Dah-Nort]

Maybe the flask was calibrated without using the tare function?

 

[Robert65]

Nah, it's just an illustration of the fact that any vessel that says "measurements are approximate" really does mean that. And every bucket or pail I've ever bought, from homebrew retailers, paint stores, etc., as well as labware, has included that disclaimer. So the OP is doing what we all should do, trust nothing, calibrate it yourself. And thanks to the guys who posted my picture, since my upload kept failing.