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Old 01-26-2011, 07:28 PM   #1
damdaman
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So I have a brew that appears to be finishing higher than expected, so I wanted to calibrate my hydrometer first to make sure that that's not the problem.

My question is when looking at the water line, there appears to be two different ways to read it. In 60* water, when looking at where the water line is flat and then looking at the hydrometer, it could be as much as .004 off. However, if I look at the water line at eye level, where the hydrometer touches the water, there's a little "hill" of water that comes up above the water line... like the hydrometer is drawing up a little bit of water right around it's edges. If I look at this line, the hydrometer is reading perfectly, or maybe .001 off, so there's potentially .004 difference between these two lines.

Does that description make sense? Which should I go by?



 
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Old 01-26-2011, 07:31 PM   #2
BendBrewer
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You read the high point of water where it touches the hydrometer. Hence why it was perfect when reading it that way.

I think my hydrometer came with instructions that directly addresses your question.

Of course I could be remembering it completely backwards.



 
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Old 01-26-2011, 07:33 PM   #3
damdaman
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Quote:
Originally Posted by BendBrewer View Post
You read the high point of water where it touches the hydrometer. Hence why it was perfect when reading it that way.

I think my hydrometer came with instructions that directly addresses your question.
Thanks! I guess I'll check my thermometer next in case I'm mashing higher than I thought.

 
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Old 01-26-2011, 07:34 PM   #4
BendBrewer
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Yep, seems like I had it backwards. Unless different hydrometers are calibrated differently.


 
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Old 01-26-2011, 07:53 PM   #5
damdaman
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Thanks for following up. Thermometer was perfect in boiling water, I retested the hydrometer and determined it's about .002 high in 60* water. Does this mean I should just subtract .002 from all my readings, or do I have to recalibrate it somehow? (not sure how I would be able to move the paper inside)

 
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Old 01-26-2011, 07:56 PM   #6
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Quote:
Originally Posted by damdaman View Post
Thanks for following up. Thermometer was perfect in boiling water, I retested the hydrometer and determined it's about .002 high in 60* water. Does this mean I should just subtract .002 from all my readings, or do I have to recalibrate it somehow? (not sure how I would be able to move the paper inside)
Just subtract .002 from all your readings.
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Old 01-26-2011, 08:01 PM   #7
damdaman
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Quote:
Originally Posted by Yooper View Post
Just subtract .002 from all your readings.
Thanks again... happens to be your oatmeal stout that I brewed on Friday that I'm concerned about. Yeast appear to be fully dormant, temp has dropped to 61*, and even with the .002 adjustment I'm at 1.020. I did dough-in too hot because I didn't account for the extra water in the mash when calculating strike temp, but I added ice and got it down to 157 in about 5 minutes (finished 155 after 60 mins).

I realize it could still drop a couple points but given the temp range for the yeast and what I've observed I'm not optimistic.

 
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Old 01-26-2011, 08:01 PM   #8
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I believe hydrometers are calibrated to be perfect at 59 deg. F, so there are lookup tables on what to ADD to your readings for the temp. of the room when the reading was taken.

I hope I didn't just go off topic.
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Old 01-26-2011, 08:04 PM   #9
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Quote:
Originally Posted by damdaman View Post
Thanks again... happens to be your oatmeal stout that I brewed on Friday that I'm concerned about. Yeast appear to be fully dormant, temp has dropped to 61*, and even with the .002 adjustment I'm at 1.020. I did dough-in too hot because I didn't account for the extra water in the mash when calculating strike temp, but I added ice and got it down to 157 in about 5 minutes (finished 155 after 60 mins).

I realize it could still drop a couple points but given the temp range for the yeast and what I've observed I'm not optimistic.
1.020 sounds fine, actually. With that recipe, and mashing it at 157, it's done. Just give it some time to "clean up" some flavors and it'll be fine.
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Old 01-26-2011, 08:06 PM   #10
damdaman
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Quote:
Originally Posted by Yooper View Post
1.020 sounds fine, actually. With that recipe, and mashing it at 157, it's done. Just give it some time to "clean up" some flavors and it'll be fine.
Will do... the sample tasted delicious.



 
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