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overshooting gravity

dankykang

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ive been overshooting my gravity by a lot, im sure its probably something I have set up wrong but I'm not sure how to narrow it down. heres my process... I copied the cloud recipe from can you brew it for mirror pond clone. i converted it for my system and the only grain change i did was to british pale ale malt. anyways it said i should have a pre boil gravity of 1.050 i ended up with 1.090 after batch sparging with about 8 gallons of water, so i added about a gallon of water and that brought it down to the 1.050 that i was looking for. then i hit my post boil gravity. this happened with my brew before this too and i ended up having to add about a gallon to get my post boil gravity but hadn't checked pre boil. according to these calculations I'm getting like 110% efficiency and i know this cant be right. any help is much appreciated.
 
It would be helpful if you posted your recipe.  You haven't given us enough information to be able to help you.
 
11 lbs 2.9 oz Pale Ale Malt 2-Row (Briess) (3.5 SRM) Grain 1 91.1 %
14.3 oz Caramel/Crystal Malt - 80L (80.0 SRM) Grain 2 7.3 %
3.1 oz Cara-Pils/Dextrine (2.0 SRM) Grain 3 1.6 %

Mash Steps


Name

Description

Step Temperature

Step Time

Mash In Add 4.08 gal of water at 165.7 F 152.0 F 60 min
◯ Batch sparge with 2 steps (Drain mash tun , 4.11gal) of 168.0 F water

◯ Add water to achieve boil volume of 6.47 gal
◯ Estimated pre-boil gravity is 1.050 SG

Boil Ingredients


Amt

Name

Type

#

%/IBU

1.03 oz Cascade [5.50 %] - Boil 85.0 min Hop 4 20.7 IBUs
1.03 oz Cascade [5.50 %] - Boil 30.0 min Hop 5 14.9 IBUs
1.03 oz Cascade [5.50 %] - Boil 5.0 min Hop 6 3.9 IBUs
1.01 oz Cascade [5.50 %] - Boil 0.0 min Hop 7 0.0 IBUs
◯ Estimated Post Boil Vol: 5.72 gal and Est Post Boil Gravity: 1.059 SG



just copied and pasted if there's a better way to do this or a preferred method let me know. thanks
 
dankykang said:
Mash In Add 4.08 gal of water at 165.7 F 152.0 F 60 min
◯ Batch sparge with 2 steps (Drain mash tun , 4.11gal) of 168.0 F water

◯ Add water to achieve boil volume of 6.47 gal
◯ Estimated pre-boil gravity is 1.050 SG


The first thing would be verifying volumes and boil-off rate.  Four gallons in mash, 4 four gallons sparge seems ok, but your original post said you sparged with eight gallons.  And you said it was 1.090 SG, but is that with total eight gallons or 12?  And then after adding one gallon to [8 or 12 gals] the gravity dropped from 1.090 to 1.050.  That's  a 44% drop in gravity from either a 12% or 8% addition in water.  So verifying all measurements would be helpful in finding the root issue.

 
so mash with 4 gallons  then sparge with 4 plus about a quarter to cover both the .o8 and .11 gallons. but after that was drained i ended up with 1.090.  so i added about a gallon and would end with about 9.25 gallons total added. i think i was right at about 6.5 gallons before i added the gallon. i did a 90 minute boil and i had that set in my recipe as well.
 
Seems like something is off.  Getting 1.090 from ~12.5# of grain in that amount of water is hard to fathom. 
 
Have you checked what your hydrometer reads in distilled water?  The water should be at the temperature printed on the white paper inside the bottom of the hydrometer.  How do you measure volume?
 
That much DME works out to 1.089 gravity. 

Are you really using grain, or are you using Dry (powered) Malt Extract?
 
Scott Ickes said:
That much DME works out to 1.089 gravity. 

Are you really using grain, or are you using Dry (powered) Malt Extract?

But, but, but...he said, "mash" and "sparge".  Does...not...compute. 
 
..........and when I first got back into brewing, after 10 years of not brewing, I had only extract brewed....and didn't know the real meaning of mash and sparge.  I used to tell people watching me brew in my kitchen that I was sparging my steeped grain bag, when in reality I was squeezing it.  I used to tell them I was mashing the grain, when I was holding my steeping bag at 150ish for 30 minutes.  I just didn't know what I didn't know back then. 

When our original poster replies, we'll learn more and be able to do a better job of helping out.  I'm probably barking up the wrong boil kettle, but the numbers were too close to be a coincidence, so I had to ask.
 
Don't get me wrong---If you turn out to be right, its brilliant.  the kind of brilliant that makes me Turn my head sideways like a confused puppy. 



 
tom_hampton said:
Don't get me wrong---If you turn out to be right, its brilliant.  the kind of brilliant that makes me Turn my head sideways like a confused puppy.

That's better than turning your head sideways and coughing....
 
Agreed... the numbers don't seem to add up.
But....I would really enjoy a 1.09 beer this holiday season when my sister in law visits..........
 
dankykang said:
just copied and pasted if there's a better way to do this or a preferred method let me know. thanks

In the recipe folder view, highlight the recipe. Click "Export Sel" in the narrow ribbon above the window.

Post that export file It'll be saved as a .bsmx file [recipe name].bsmx

 
here's the recipe. and yes i'm batch sparging all grain in a 10 gallon cooler. I do have dme on hand but only in case I end up a little on the low side of the gravity i'm shooting for.
 

Attachments

  • mirrorpond.bsmx
    18.1 KB · Views: 149
  • mirrorpond.bsmx
    18.1 KB · Views: 153
checked the hydrometer in actual distilled water. not tap water not ordinary bottled water. and it checks out. I made sure that the hydrometer wasn't stuck on the side of the glass tube thing it goes in when I was brewing. so heres my whole process. I started the strike water (4 gallons) to 175f put it in the cooler (mash tun) and stirred it until it dropped to its desired temp of 165 then stirred in the all the grains and made sure I was at the 152f I wanted to mash at. I put the lid on and then came back opened it roughly every 15 minutes gently to make sure everything was broke up no hot spots no dough balls etc. I placed the lid back on each time and didn't check what temp it was at the end. When the hour was up I drained from the ball valve on my mash tun into my boil kettle. I then added the sparge water (4.25 gallons) that was heated to 168f. I let that sit for ten minutes and drained that into the kettle coming up with about 6.5 gallons of water. I made sure that i stirred it together and then used the ball valve on my kettle to add some wort to the glass tube for my hydrometer. i chilled this to 80f and took a reading of 1.090. my hydrometer is calibrated at 60f so that would technically be 1.092 but i was keeping it simple in my original post. so i added about a gallon of water to the boil kettle and then stirred it up to make sure it was mixed well. i got a reading of 1.050 like i was shooting for. i then boiled for 90 minutes and hit my post boil gravity of 1.059.
 
I'm wondering if it is your way of pulling a sample for your hydrometer.  Your highest gravity wort goes into the kettle first.  Then the lower gravity wort from your batch sparge goes on top of that.  If the higher gravity wort from your first runnings is staying mostly separated from your batch sparge runnings, you'll have the higher gravity wort at the bottom of your kettle and the lower gravity wort at the top of the kettle.  You're pulling your sample from the valve at the bottom of your kettle, so you might be getting the high gravity first runnings only.

On your next brew, try stirring lightly for a little bit before pulling your wort sample.  I'm betting that will make all the difference and you'll find your quite close to hitting your actual target gravity. 

In addition, you added 1 gallon of water to 6.5 gallons of water and got a drop from 1.090 to 1.050, which is way too much of a drop for that small change in volume.  The numbers just don't add up, if your wort was equalized on gravity throughout the wort.
 
dankykang said:
i chilled this to 80f and took a reading of 1.090. ...i added about a gallon of water... got a reading of 1.050 like i was shooting for. i then boiled for 90 minutes and hit my post boil gravity of 1.059.

Something is wrong with that initial gravity reading. I don't think it could have been any higher than 1.060 based on the volumes you're describing. To me, 1.090 is a red herring. [EDIT: Scott posted my exact thoughts, that the wort wasn't fully mixed.]

Your recipe doesn't show the actual pre and post boil volumes or gravities. What's left is volumes based on your description and what BeerSmith calculates. I'm figuring that after sparging, you have the stated 6.5 gallons and you added a gallon to get it down to 1.050. That tells me that the lower volume couldn't have been 1.090 because it'd have taken about 5 gallons to dilute that out.

Getting 1.050 at a preboil volume of 7.5 gallons is about 83% mash efficiency. Quite plausible. Very respectable. Use that efficiency as your brewhouse efficiency number, since you don't have any trub losses recorded.
 
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