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Old 12-31-2011, 03:50 PM   #1
Jewrican
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I have a keggle with a false bottom. 2 gallons of water sits under the false bottom in the tun.

I made a stout yesterday with 21 lbs of grain and with 2 gallons of dead space in Beersmith it said to use 9 gallons of water which is nearly 1.7 quarts per lbs.

Now my question starts here. Does dead space in Beersmith mean i cant get 2 gallons of liquid or does that mean that 2 gallons dont touch the grain?

My next thing is that with the same brew sheet, it said that i need 10.48 gallons of wort pre boil, but afterwards I would have 7.28 gallons post boil (90 minute boil)

Why would this be with a 6 gallon batch? Shouldn't i have 6 gallons (or maybe slightly more than that) post boil? I stuck the rest of the wort in another fermenter to just make more.

So my issues are:
* does dead space mean not in contact with grain or is it that it is not drainable?
* Why would it state my post boil is 7.5 gallons when it is a 6 gallon batch?
* Finally, it says post boil gravity should be my OG according to the recipe which is 1.092. But it says that after the boil (7.28 gallons) should be 1.092.

My brewday was less than perfect (thermometer deceived me and temp was over 165 ) so I would not be shocked with a lower OG but i measured 1.070 @ 72 degrees. That is a lot... i am wondering if the extra liquid is causing a bit of that.

If i boiled off another 1.28 gallons to make the 6 gallons, what would my OG have been then? Just curious.
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Old 12-31-2011, 04:16 PM   #2
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In regards to the deadspace issue; This is the amount of wort that you will lose to piping and the bottom of your MT that you cant transfer. To figure out this amount add a measured amount of water to your system. Pump it from your MT to your BK and then into a fermenter. Remeasure how much you now have. The amount you lost is the deadspace amount. It is likely that this amount is around a quarter of a gallon or less.

There is a lot of good info on Beersmiths Website.
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Old 12-31-2011, 04:23 PM   #3
Jewrican
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gotcha. so i know it is nearly 2 gallons under my false bottom but nearly nothing that i cant drain. so i just need to stop relying on beersmith for that.

I think i will just play it by ear until i get a decent looking mash consistency and then sparge whatever is left for my pre-boil amount... which takes me to the rest of my concerns with that beersmith brewsheet.. why the heck i have so much pre and post volume wort.
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Old 12-31-2011, 04:26 PM   #4
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Dead space is the liquid that remains in your keggle after you drain it. Leaving two gallons behind will have a significant impact on your efficiency. That's probably why you had such a low OG. If you don't have one already, I'd install a dip tube.

Edit: Nevermind, I walked away while the previous posts were added--OBE.

Beersmith's calculations for water take some work to get dialed into your equipment. You've probably got something set wrong, click on equipment details and play with them.

If you had boiled down to 6 gallons you'd have a gravity around 1.084, I think.

Finally, mashing at 165 will likely give you a lot of unfermentable sugars. You're probably going to have trouble getting your FG down where you want it.
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Old 12-31-2011, 09:47 PM   #5
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yeah i am thinking my FG will be rough... not very happy about it. i thought about not using a stout as my first beer cause they are typically more expensive, but i really wanted one...

well hell, what can you do. it is what it

I should have looked at the brew sheet to see 7.xx gallons after boil and known something was up... ill have to back track a bit.

oh well.. you brew and you learn... its a hobby which is equivalent to a money pit right?
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Old 12-31-2011, 09:49 PM   #6
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Calculate your strike based on 1.25qt/lb initially, then add 2 gallons.
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Old 12-31-2011, 09:53 PM   #7
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Calculate your strike based on 1.25qt/lb initially, then add 2 gallons.
Makes sense and will do! Thanks Bobby
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Old 12-31-2011, 10:19 PM   #8
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Quote:
Originally Posted by Jewrican View Post
yeah i am thinking my FG will be rough... not very happy about it. i thought about not using a stout as my first beer cause they are typically more expensive, but i really wanted one...

well hell, what can you do. it is what it
You never know, it could come out fine. I have a Porter that stopped around 1022 that tastes great. I'll be having a couple of them tonight.
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