Why does my gravity aways seem to be off?

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Bulls Beers

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Never fails. Either I'm off on my OG or FG. I just brewed a Pilsner, my OG was suppose to be Between 1.040-1.042. Mine was 1.052. I've done 8 batches so far and most of my finish gravites never hit it's target. usually off by 4-6 points.

Any suggestions?
 
could be volume...make sure for a five gallon batch you are EXACTLY at five gallons.

for most extract brewers the problem is that the sugars settle so you don't get a good reading. you need to mix it thoroughly just before you take the sample so you don't get a diluted sample or a sample with a heavy mix of sugars.

if you ARE doing extract, i would just go with the projected gravity and trust it...it will have exactly how much sugar you put into it.

EDIT: Final gravity can depend entirely on yeast attenuation, ingredients, mashing temperatures and a number of other things. you generally did not get anywhere near my projected FG when making extract batches. as long as it doesn't taste too sweet, you're in your attenutation range (usually ~70%) and there is no activity for several days, you are ready for the next stage.
 
Have you checked your hydrometers accuracy?

Using distilled water at 60F it should read 1.000.
 
DeathBrewer said:
could be volume...make sure for a five gallon batch you are EXACTLY at five gallons.

for most extract brewers the problem is that the sugars settle so you don't get a good reading. you need to mix it thoroughly just before you take the sample so you don't get a diluted sample or a sample with a heavy mix of sugars.

if you ARE doing extract, i would just go with the projected gravity and trust it...it will have exactly how much sugar you put into it.

EDIT: Final gravity can depend entirely on yeast attenuation, ingredients, mashing temperatures and a number of other things. you generally did not get anywhere near my projected FG when making extract batches. as long as it doesn't taste too sweet, you're in your attenutation range (usually ~70%) and there is no activity for several days, you are ready for the next stage.

Yes. I'm doing extract batches. I brewed with 2 gallons and added 3 1/2 in the primary for any water loss.
 
partial boil extract batches take at least 10 minutes of constant stirring to become a homogenous mixture.

so, your hydrometer samples aren't diluted for your OG reading, and they come out thicker than they should, and thus a higher OG reading.

if you're following an extract recipe and you top off to 5 gallons, you cannot miss your OG range....just assume its correct.

For FG readings, those are accurate as long as your hydro is calibrated and you're adjusting for temperature differences. your FG should be close to what the recipe states. a couple points either way is no big deal. if you're off by 10-20 points...somethings up...probably a stuck/stalled fermentation.
 
Temperature could be another factor. At 68F (if your hydrometer is calibrated for 60F) you have 2 points difference right there.
 
malkore said:
if you're following an extract recipe and you top off to 5 gallons, you cannot miss your OG range....just assume its correct.

I have to disagree with this partially because I've had a lot of extract batches that are off the mark on the OG. I think a lot of recipes expect more gravity points than the malt extract can deliver. A good example is in Clone Brews where you have one recipe w/ an SG of 1.052 w/ 6# of DME and then another recipe with a range of 1.056 to 1.060 with the same 6# of DME.

Now I always try to plus up the extract by a small amount and I always hit the OG but sometimes I do come out with a slightly stronger beer. I did a Red Hook ESB clone and it came in at 1.060 so it will be a little stronger than the real deal.:drunk: :tank: :mug:

Regards,
Al
 
i wouldn't trust anything clone brews says. you can make some good beer with their recipes, but it'll never be on mark with what you're trying to clone. it's more a "learn the style" book.

volume is key, too. pour 1 gallon at a time into your fermentation vessel and make marks all the way. i make a 5.25 and 5.5 gallon mark, too. that way, i can always be spot on with my gravity and if i need to add water to drop it, i can.

and yeah, mix the s*** out of it before you take a sample.

and no, you will CAN NOT miss your OG range if you have the correct volume and the correct amount of sugars/extracts. the only thing that could be wrong is your recipe specifications, unless a mistake was made in the process.

:mug:
 
DeathBrewer said:
...volume is key, too. pour 1 gallon at a time into your fermentation vessel and make marks all the way. i make a 5.25 and 5.5 gallon mark, too. that way, i can always be spot on with my gravity and if i need to add water to drop it, i can.

...

I finally marked 5 gallons on one of my 5 gal and my 6.5 gal carboys I'll add the extra gallon marks when mine become free :). After reading way off on the 8-8-08 RIS, i way watered it down in my 6.5 gal carboy :(

Next step, i need to get myself something better than a 2 quart plastic pitcher to measure out water. I'm hopeing in March to get a bigger brew pot though, so i can start doing full boils and that should correct any top off/mix OG reading errors :).
 
DeathBrewer said:
i wouldn't trust anything clone brews says. you can make some good beer with their recipes, but it'll never be on mark with what you're trying to clone. it's more a "learn the style" book.

Man, I sure do agree with that 100%. Clone Brews was a real disappointment when I first looked at it.


TL
 
Hard to beat gallon milk jugs for measuring water. Profit margins and government regulations being what they are, the dairy industry is very precise in their production. If a 2 quart pitcher is off by 3 ounces, your gravities would be off by 10% either way.

LME does vary, both in sugar content and fermentability. DME has a more consistent sugar content from one manufacturer to another, but fermentability will still vary.
 
TexLaw said:
Man, I sure do agree with that 100%. Clone Brews was a real disappointment when I first looked at it.


TL

Hey Tex, I've found this out the hard way but do you know of a good recipe book for us novice types? I make the SNPA "Clone Brews" recipe regularly but I do tweak it a bit. It really does'nt taste like Sierra but it does make a very good PA.

Regards,
Al
 
My thinking is I didn't mix it very well. I added 3 gallons of water to my primary. i then added the wort after it cooled.
 
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