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Old 10-21-2009, 12:23 PM   #1
Bioguy1975
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Sep 2009
N. Illinois
Posts: 28


... no, not antgravity!

So, for four days straight, my final gravity in my primary fermenter is at about 1.020. (taking samples with a sample thief.) I never took my original gravity reading, as this is my first batch, and in my rush to ferment and in my excitement, etc etc etc.

Per the kit, my OG was supposed to be 1.052, and my final gravity at 1.013.

I've done a few swirls of my primary... I am still getting bubbles every now and again in my airlock, but my stable gravity reading tells me that most likely fermentation is over. Or is it?

I am using Wyeast 1762, temperature has been stable at 68degF.

My only concern is my total volume... I know I didn't take into account boil-off, so I may have significantly less than 5 gallons. I have a 6.5 gal glass carboy as my primary fermenter; it is a total of 22 inches tall from the bottom of the carboy to the top of the spout - my total beer volume is 10 inches tall. Given a 12 inch diameter of the carboy, (and using volume of a cylinder equation) I estimate a pi(r^2) x height to give me 1131 cu in, or just about 4.89 gallons. Which means I'm about 12 ounces shy of the full 5 gallons.

My intent is, once primary is finished, to rack into a 5gal glass carboy for secondary for two weeks.

My thought is, perhaps I need to add more water to the system? 12 oz seems like a small amount to lower my gravity by 0.007. But I also don't want to blow bottles! Let me know if you need any more information.
__________________
6.5 gal Glass Primary: Air, waiting to be thoroughly cleaned
5.0 gal Glass Secondary 1: Air, waiting to be thoroughly cleaned
5.0 gal Glass Secondary 2: Air, cleaned
5.0 gal Glass Secondary 3: Air, cleaned
On Deck: Fat Tire Clone

Bottled, waiting: Nada
Bottled, ready: Black Forest Stout, Vanilla Porter

 
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Old 10-21-2009, 12:43 PM   #2
stale
 
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Mar 2007
TRI-CITIES, WA.
Posts: 137

Quote:
Originally Posted by Bioguy1975 View Post
... no, not antgravity!

So, for four days straight, my final gravity in my primary fermenter is at about 1.020. (taking samples with a sample thief.) I never took my original gravity reading, as this is my first batch, and in my rush to ferment and in my excitement, etc etc etc.

Per the kit, my OG was supposed to be 1.052, and my final gravity at 1.013.

I've done a few swirls of my primary... I am still getting bubbles every now and again in my airlock, but my stable gravity reading tells me that most likely fermentation is over. Or is it?

I am using Wyeast 1762, temperature has been stable at 68degF.

My only concern is my total volume... I know I didn't take into account boil-off, so I may have significantly less than 5 gallons. I have a 6.5 gal glass carboy as my primary fermenter; it is a total of 22 inches tall from the bottom of the carboy to the top of the spout - my total beer volume is 10 inches tall. Given a 12 inch diameter of the carboy, (and using volume of a cylinder equation) I estimate a pi(r^2) x height to give me 1131 cu in, or just about 4.89 gallons. Which means I'm about 12 ounces shy of the full 5 gallons.

My intent is, once primary is finished, to rack into a 5gal glass carboy for secondary for two weeks.

My thought is, perhaps I need to add more water to the system? 12 oz seems like a small amount to lower my gravity by 0.007. But I also don't want to blow bottles! Let me know if you need any more information.
will probably need to know when you started in primary. 1 wk? 2? 3?

 
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Old 10-21-2009, 01:08 PM   #3

A couple musings:

1. If you've got a 6.5 gallon carboy and it is less than half full, then I think you've got around 3.5 gallons or less, not the nearly five that your math exercise led you to deduce

2. If your volume is much lower then you thought, then that's why your final gravity is high

3. If the above is correct, then I wouldn't worry about bottle bombs; what's left in your beer is the unfermentable sugars.

Cheers,

 
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Old 10-21-2009, 01:11 PM   #4
Snyder
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Dec 2008
Perrysburg, OH.
Posts: 88
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I'm a bit of a noob myself, but I did the NB fat tyre clone too and had the same issues. Fermentation seemed to sputter around 1.020. Did the swirl, and got it down to 1.016. Overall I left it in the primary for 4 weeks. I went ahead and bottled. I'm about 5 days in, and no bombs yet! I wouldn't think that 12 oz. would throw your gravity off. I'm sure someone with more experience will chime in.

 
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Old 10-21-2009, 01:31 PM   #5
Bioguy1975
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Sep 2009
N. Illinois
Posts: 28

To stale's question - primary was started on Oct 11, so this is day 10.

To Pappers and Snyder - this is my deduction as well. I think I'll toss into my secondary this evening. I'm going to see if I can settled some of the extra 'stuff' out, but my guess is that this beer is going to be a bit on the heavy side.

To everyone - what impact will a higher gravity have on the flavor of the final product?
__________________
6.5 gal Glass Primary: Air, waiting to be thoroughly cleaned
5.0 gal Glass Secondary 1: Air, waiting to be thoroughly cleaned
5.0 gal Glass Secondary 2: Air, cleaned
5.0 gal Glass Secondary 3: Air, cleaned
On Deck: Fat Tire Clone

Bottled, waiting: Nada
Bottled, ready: Black Forest Stout, Vanilla Porter

 
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