How do you measure your volumes?

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ashyg

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I just did my first all-grain batch on my new setup and wound up only putting 4.5 gallons in my primary.

Recipe:

Some Kind of Bitter

8 lbs 2 row
.5 lb Caramel 60

60 min boil
1 oz Fuggles FWH
.5 oz Fuggles 60m
.5 oz Cascade 60m
.5 oz Fuggles 30m

Safale 04

My mash was 3.5 gallons, my sparge was 3.75, which should mean my total volume was 7.25 gallons. Figure 0.13 gallons/lb lost to grain absorption means 1.105 gallons lost, meaning 6.15-ish gallons pre-boil. Loss to mash tun dead space is almost negligible, I measured it at 125 mL. Boil was 60 minutes, 15% boiloff per hour, about 1 gallon would boil off, so I should have 5 gallons left in my kettle.

But I didn't. I dumped pretty much everything from the kettle into my primary(including a lot of trub because I wanted all the sweet sweet wort I could get) and it only came up to the 4.5 gallon mark on my carboy. What gives!

Another point of confusion:

My pre-boil gravity was 1.022 at 115 degrees fahrenheit. I plugged that into a calculator and it says it would be 1.032 at 60 degrees. Post-boil, post-chill gravity was... 1.032 at 70 degrees. What? How can I have the same gravity pre and post boil if almost a gallon of liquid was boiled off? Is it because I really, really shouldn't try taking gravity measurements at 115 degrees and using a formula to adjust?

My efficiency was also way off -- 61% according to Beer Alchemy. Yeek. I think that's because I had difficulty controlling the mash temperature in my mash tun. I preheated it with about a gallon of almost boiling water for maybe 10 minutes, tossed in my grains, and then threw in strike water at 166 degrees. Temperature dropped to 152(YES!) and stayed there for about 10 minutes, then slid down to 148. Uhoh. I started collecting wort from my mash tun, pouring it into the kettle I was heating my sparge water in, and recirculating to bring it back up to 152. Got it at 152 and it held for another 10 minutes, then dropped back down. This is with a Coleman Xtreme cooler, which I thought was supposed to be pretty good for holding temperature, but I had a lot of difficulty!

Either way... the gravity is 1.032, the attenuation of the yeast is about 73%, I can expect a FG around 1.009 and about 4 gallons after racking off the cake of a 3.2% ish session beer. RDWHAHB I suppose... but I want to hit my targets next time :)
 
Oh... so the reason I asked how you measure your volumes... I don't trust that my measurements were accurate. I used a 2 qt pitcher. I don't believe in it any more. What do you folks use for accuracy?
 
I basically measured the diameter of my brew kettle, calculated the volume for 1,2,3,4,5 gallons in regards to height, marked a stick with said heights and immerse the stick in the wort or water. I then check the level, just like I do with the oil in my car and I can always do some "on the fly calculations" to correct my volumes. Easy, cheap and foolproof. Way more convenient than using some kind of receptable and scooping for 15 minutes.

I'm meaning to do the same thing for my bucket fermenters, but I just account for .5 gallon of trub loss when racking/bottling instead. It's pretty mucha given you cannot use this method for anythign that is tapered or uneven in shape (unless you account for that initially in your stick marking, but I'm no fancy pants mathematicians here).
 
I'm with JFR - I marked my brew spoon at the level I need to do an hour boil (for me, that's 6.5 gallons, to end up with 5.5 gallon batch). So, I mash at the suggested temp and volume, mash out, then batch sparge until I reach the volume I want, according to the mark on my spoon. Damn near foolproof. Not very scientific, doesn't involve any formulas or calculations, which fits my approach.
 
Calculated my dip stick by measuring the water by wieght, its dead on too.
Put your kettle on the scale, fill until you hit 2Lbs, that would mark 0.25 gallons in your kettle, fill another 2Lbs, and mark the 0.50 gallon line, and so on until your kettle is full.


8oz. of water by volume = 8oz. water by weight
 
Unbelievable, I thought I was the only one to use the "dipstick" method. "I ain't no mathematician neither", but Gregscsu,jfr and Pappers method works every time. I always brew a 6 gallon batch figuring I will end up with 5 gallons, do to losses in the boil and trub sucking up some wort. I like the word dipstick, J .
 
I'm assuming like most things water expands with heat? Is the expansion negligible?
 
I think Beersmith accounts for 4% loss when the wort cools down, but since I always top off, I don't really care about that figure. I just measure my stuff when it is going in to mash and the final result. I don't measure my sparge water or anything since sparge until I'm at my boil volume.
 
Calculated my dip stick by measuring the water by wieght, its dead on too.
Put your kettle on the scale, fill until you hit 2Lbs, that would mark 0.25 gallons in your kettle, fill another 2Lbs, and mark the 0.50 gallon line, and so on until your kettle is full.


8oz. of water by volume = 8oz. water by weight


Sorry, but 1 gallon water weighs 8.33 lbs according to http://ga.water.usgs.gov/edu/waterproperties.html so 8oz. of water by volume = 8.33 oz. water by weight, but they don't specify the temperature.

I agree that weight is the way to go if you want accuracy, as it accounts for temperature differences. (The volume at boiling point is about 4% greater than the volume at pitching temperatures.)

-a.
 
I think taking hydrometer samples when the wort is above about 90 degrees is a waste of time. I know they have correction tables, but I've never had an accurate reading at 100 or above, even with the correction tables. At 90 degrees, the correction tables work great. I recommend cooling the sample in an ice bath, and then checking it.

Keep in mind that in order to be able to predict your post- boil OG from your preboil SG, you'll have to have accurate volume measurements. For example, if you have exactly 7 gallons at 1.040 preboil, and you end up with exactly 5 gallons postboil (chilled), your SG would have to be 1.056. (If my math is right- I drink, you know. :drunk:)

If you don't have an accurate volume measurement, you can't really guess your predicted OG from the preboil volume.
 
did you plug the temps of your gravity readings into beer alchemy? it adjusts the gravity automatically for you based on the temp you input. Also need to enter what temp your hydro is calibrated at.

As for measuring, I have a sight glass on my HLT that I marked in half gallon intervals using a large Pyrex liquid measure cup. I also marked the handle of my mash paddle and the outside of my brew kettle, calibrated using the same method.
 
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