Kettle and Fermenter Volume Calibration Markings

Mike at Bay

Mike at Bay

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As you'd expect both my SS Brewtech kettle and fermenter have gallon and liter markings. I work in gallons. My question is how do you dial in volumes using these markings. Once you have wort you can't really move the stuff from one measuring vessel to another without risk of spillage or contamination.

Strike volume (BIAB) is not an issue because I can measure out gallons using a "scientifically" calibrated scale on the pitcher. I have done a test boil off with the kettle so I know I normally boil off 1.7 gallons. However, that is where the science ends and the estimation begins for me. Can I get close.....sure...."that looks like about 5.8 gallons". I take pics of all the stages of the brew in the kettle and fermenter so I can torture things after the brew.....but with these markings angles and level vessels make a difference.

And as you'd expect even slight differences in volumes change efficiency and gravity measurements.

Any advice (like don't get hung up on ounces)?

Signed, Wannabe Chemist. :)
 
I marked a dowel at 1/2 gallon increments , you can get more precise if needed
 
Donoroto said:
Water expands with heat, so the markings I have get less and less accurate as temperature increases, and the bubbles in the boil throw it way out, so I just brew with ‘my eyes closed’ (figuratively).
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That's what I'm talkin' about!!!!! LOL. Good advice. I am just hoping to get PreB, PostB and Fermenter volumes to be a little more accurate.
 
I don't get too sciency about precise water volumes either, the Brewzilla level markings are off by an amount that seems to work for me.
 
The really sciency way to do it is by weight. The apparent volume changes with temperature fluctuations, but the weight does not change as the volume changes due to temperature.
 
Mike at Bay said:
That's what I'm talkin' about!!!!! LOL. Good advice. I am just hoping to get PreB, PostB and Fermenter volumes to be a little more accurate.
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Many here advise to brew for gravity, not volume.

I do check gravity, but do little or nothing about it if there is something off a bit. Maybe a bit less or more sparge water.
 
Donoroto said:
Many here advise to brew for gravity, not volume.

I do check gravity, but do little or nothing about it if there is something off a bit. Maybe a bit less or more sparge water.
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Yeah, this is a good approach since there are so many variables that can play with your targets and expected results. Trying to hit them can lead to frustration and you're doing this for fun...right? Being is the ballpark is a better goal IMHO. You want to know your starting gravity so you can figure out the FG and know that you were at least in the cheap seats and not in row Z 15 of the parking lot!
Just remember.....malted barley wants to become beer!
 
Really wouldn't get that worried about it.

You don't brew for volume, you brew for gravity! When done mashing and boiling, test the gravity and add water to fix it. Get the gravity right and the beer will turn out the way you want it. Better good beer that is off a bit in volume, than correct volume and compromised beer
 
Thanks all! Agree....I am not brewing specifically to the volume per se but the equipment profile and thus recipes are built on assumptions that I would like to be able to validate with some accuracy. In theory, the more I can measure with confidence, the less "why did that happen?". :)

I recently started logging numbers into a spreadsheet so I can track averages over time. I am going to go the dipstick route for now, I think that should help.
 
At our scale, there are so many variables that contribute to variance in the results. It hard to nail it down to one or two things. I tried for years, now i just accept that i may get a really good efficiency one day and not the next and it makes my brew day happier
 
Consider that the markings on you kettle are off.
Now consider that while they are off, they are consistent, even a constant really.
It isn't a critical aspect of brewing for water volume to be exact. You can always top up, or boil a little longer to get your desired gravity.
There are finer points of brewing to be precise about, IMHO
 
the only thing I wory about is ending boil mark, I have starting boil marked just in case I sparge too much
 
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I think Mike is in Florida. Boil off rates are fairly predictable in Florida unless you have a very dry, cold winter day - A little off here and there, but not much to worry about at our level. I am almost exactly a gallon an hour in my 16-gallon kettle.
 
Sandy Feet said:
I think Mike is in Florida. Boil off rates are fairly predictable in Florida unless you have a very dry, cold winter day - A little off here and there, but not much to worry about at our level. I am almost exactly a gallon an hour in my 16-gallon kettle.
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Yep. The beer just hangs in the air. LOL
 
Take notes, repeat everything consistently or only change one variable at a time, take more notes.
Id start with your favorite recipe and plan to brew it at least 3 times in a row, by then you should have it dialed in with enough notes to go by. Efficiencies, evaporation losses, absorption rates, kettle and fermentor losses etc.
I think brewing inside removes the biggest variable, but for most thats not an option. If you can, do it, if not, try to repeat the exterior setup as close as possible, keeping an eye on the evaporation rate and adjusting at flame out. Pre boiled water for tip off, or extend the boil if need be.
Again by the 3rd time, you'll have it dialed in.
Cheers,
Brian
 
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