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Old 03-25-2007, 11:04 PM   #1
Cregar
 
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Did a search and couldn't find anything on it but I just checked the calibration of my hydrometer and at 60 degrees its showing 1.002.

So, does that mean I have to adjust my readings by minusing .002 from my readings.

example: currently my FG is reading 1.018 at 70 degrees... so, I minus .002 from 1.018 to equal 1.016... then adjust for temp of water (70 degrees)... so my adjusted FG should be 1.017.

Is this correct??



 
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Old 03-25-2007, 11:06 PM   #2
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Adjust for temperature first and then subtract. But yeah you've got it.


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Old 03-25-2007, 11:15 PM   #3
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cool... thanks.

This is a hefe I have currently in the primary (1 week as of today) Looks like fermentation has stopped... no bubbles. Why would the gravity be so high still?

My software shows it should be around 1.012.

I made a 2 quart starter... and aerated the hell out of it. Temp held at a even 68 degrees.

You think it will drop another 5 point in another few weeks?

 
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Old 03-25-2007, 11:55 PM   #4
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yeah I just recently checked mine; turns out it's 4 points off...




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Old 03-26-2007, 12:36 AM   #5
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I guess that means everyone should calibrate the hydrometer before using. Might save a alot of headaches


 
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Old 03-26-2007, 01:23 AM   #6
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In the long run it seems like +_ 2 or even 6 points isn't going to make that much dif anyway. It is nice to know were you are but It is just beer afterall.

 
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Old 03-26-2007, 01:35 AM   #7
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Maybe your's was calibrated to 68? That would be about a point difference.
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Old 03-26-2007, 03:06 AM   #8
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Quote:
Originally Posted by Brewsmith
Maybe your's was calibrated to 68? That would be about a point difference.
It says its calibrated at 60 degrees. Oh well... I will let it go another week and check it again.

 
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Old 03-26-2007, 03:34 AM   #9
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I'm going to rain on this parade a little...apology in advance...

Unless you're really excited about hitting your predicted numbers EXACTLY, hydrometer calibration is a bit of a moot point. To measure ABV, you simply take the difference between OG and FG and apply a correction factor. The actual readings don't need to be accurate as long as they're consistent (same temp, or same temperature correction applied). To determine if fermentation is complete, you just need a hydrometer reading that is unchanged over time. Again, the exact specific gravity isn't required. RDWHAHB!

[hypocrite]
Now read the steam mashing thread and call me a hypocrite (a bunch of anal retentive math there). I suppose knowing if your hydrometer is accurate or not is a bit appealing to those of us who are a bit obsessive...
[/hypocrite]
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Old 03-26-2007, 04:09 AM   #10
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Quote:
Originally Posted by Yuri_Rage
I'm going to rain on this parade a little...apology in advance...

Unless you're really excited about hitting your predicted numbers EXACTLY, hydrometer calibration is a bit of a moot point. To measure ABV, you simply take the difference between OG and FG and apply a correction factor. The actual readings don't need to be accurate as long as they're consistent (same temp, or same temperature correction applied). To determine if fermentation is complete, you just need a hydrometer reading that is unchanged over time. Again, the exact specific gravity isn't required. RDWHAHB!

[hypocrite]
Now read the steam mashing thread and call me a hypocrite (a bunch of anal retentive math there). I suppose knowing if your hydrometer is accurate or not is a bit appealing to those of us who are a bit obsessive...
[/hypocrite]
Great post.com



 
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