Quantcast

Hydrometerly Challenged

HomeBrewTalk.com - Beer, Wine, Mead, & Cider Brewing Discussion Community.

Help Support Homebrew Talk:

dutch101st

Well-Known Member
Joined
Mar 3, 2009
Messages
216
Reaction score
1
Location
Roseville, CA
Ok, I am still struggleing with the concept of reading a hydrometer. Smart enough guy, just can't wrap my brain around it.

Anyone have any simplified instructions on how best to read it? Pictures always a plus.
 

Bobby_M

Vendor and Brewer
HBT Sponsor
Joined
Aug 3, 2006
Messages
24,787
Reaction score
3,452
Location
Whitehouse Station
[ame=http://www.youtube.com/watch?v=xtQt7HiObuU]YouTube - Hydrometer - Brewing Beginner Series[/ame]

[ame=http://www.youtube.com/watch?v=KaonMYRODks]YouTube - Brewing with Bobby M Refractometer vs. Hydrometer[/ame]
 

wendelgee2

Well-Known Member
Joined
Dec 5, 2008
Messages
324
Reaction score
3
Location
New York, NY
Two questions:
The "quick guide" suggests getting rid of all bubbles by pouring the sample back and forth. Will a carbonated sample read as less dense, or is that just so the bubbles don't "grab on" at the top and give you a false reading.

also, my hydrometer never bobs in the middle of the sample like that, it leans to one side or the other, is that a problem?
 

BierMuncher

...My Junk is Ugly...
Lifetime Supporter
Joined
Jan 17, 2007
Messages
12,443
Reaction score
974
Location
St. Louis, MO
This is an original gravity reading of a Kolsch at 1056:

Hydrometer.JPG

This is an original gravity reading of a light haus ale at 1038.
clearwort1.jpg

As the beer ferments, the liquid becomes thinner and the hydrometer will begin to sink. Eventually, the hydrometer will sink until they read a final gravity.

In the first case (1056) let's say it finishes at 1.012.

Take 1056 (beginning) and subtract 1012 (finishing) and multiply the difference by 131. In this case, 44x131 = 5.764, or 5.8%.

No need to pour sample back and forth, just bob the hydro up and down a few times to knock any CO2 bubble off the glass so it doesn't float artificially high.
 

cactusgarrett

Well-Known Member
Joined
Apr 8, 2008
Messages
1,827
Reaction score
520
Location
Madison, WI
This is an original gravity reading of a Kolsch at 1056:

This is an original gravity reading of a light haus ale at 1038.
To me, in order to get a better view, those tubes look like they should be viewed from the side more in order to see where the bottom of the meniscus is at. As the liquid starts to "come up" on the hydrometer glass, from those angles i would be more inclined to call those closer to 1.060 and 1.040, respectively. Just my two cents.
 
OP
dutch101st

dutch101st

Well-Known Member
Joined
Mar 3, 2009
Messages
216
Reaction score
1
Location
Roseville, CA
Good deal...thanks fellas.

I couldnt get over the 1.000 and then reading the 30, 40, and 50 graduated increments. I see how it is formatted now. Thank you again!
 

rico567

Well-Known Member
Joined
Apr 28, 2008
Messages
3,016
Reaction score
97
Location
Central IL
....which illustrates the difficulty, if you've never actually been in a hands-on lab situation and received instruction on how to read the thing. Luckily, I had all that stuff in college. In this case, the camera very well MAY be lying, compared to eyeballing the hydrometer level and up close.
 

jgln

Well-Known Member
Joined
May 20, 2008
Messages
3,521
Reaction score
64
Location
Southern, NJ
This is an original gravity reading of a Kolsch at 1056:

View attachment 10289

This is an original gravity reading of a light haus ale at 1038.
View attachment 10290

As the beer ferments, the liquid becomes thinner and the hydrometer will begin to sink. Eventually, the hydrometer will sink until they read a final gravity.

In the first case (1056) let's say it finishes at 1.012.

Take 1056 (beginning) and subtract 1012 (finishing) and multiply the difference by 131. In this case, 44x131 = 5.764, or 5.8%.

No need to pour sample back and forth, just bob the hydro up and down a few times to knock any CO2 bubble off the glass so it doesn't float artificially high.
I do record OG and FG readings but I am not overly concerned about being exact. I brew kind of like I cook, not doing much exact measuring once I get my recipe down and I don't mind a bit of variance.
With that said, isn't it just as easy to calculate ABV by using the alcohol scale on the other side of the hydrometer and take an original reading of say 7%, then when done fermenting take the next reading, say 3% and assume then my ABV to be 4%?
Just trying to suggest a very simple method with a tad bit easier math. Am I wrong doing it that way?
I am asking you as I do respect you knowledge on brewing.
 

HSM

Well-Known Member
Joined
Jan 23, 2009
Messages
460
Reaction score
9
Location
McMurray, PA
To me, in order to get a better view, those tubes look like they should be viewed from the side more in order to see where the bottom of the meniscus is at. As the liquid starts to "come up" on the hydrometer glass, from those angles i would be more inclined to call those closer to 1.060 and 1.040, respectively. Just my two cents.
That's what it looks like to me as well. In the end if you read it the same way for OG/FG you'll have same results.
 

BierMuncher

...My Junk is Ugly...
Lifetime Supporter
Joined
Jan 17, 2007
Messages
12,443
Reaction score
974
Location
St. Louis, MO
...isn't it just as easy to calculate ABV by using the alcohol scale on the other side of the hydrometer and take an original reading of say 7%, then when done fermenting take the next reading, say 3% and assume then my ABV to be 4%?
Just trying to suggest a very simple method with a tad bit easier math. Am I wrong doing it that way?
I am asking you as I do respect you knowledge on brewing.
It certainly is a way to determine ABV, if that's all we're looking for. For me, the alcohol content is a result of a procedure.

Using the gravity readings helps me determine my efficiency and improve my procedure. Since recipes are built around target starting and finishing gravites, that scale is a better tool for improving brew methods.
 

bad coffee

Well-Known Member
Lifetime Supporter
Joined
Jun 28, 2008
Messages
5,152
Reaction score
498
Location
NYC
You can give the hydrometer a quick spin in the tube and the bubbles will slough off the hydrometer.

I've always read the bottom of the meniscus, then actually read the destruction sheet of my new $5.95 hydro from Midwest.

It actually says to read at the top of the meniscus! So for my last brew, I did read the top. As long as I remember to read the top when I do the FG, it should be fine.

But then again, I jsut bought a refracto, so I'll most likely be using that.
 
OP
dutch101st

dutch101st

Well-Known Member
Joined
Mar 3, 2009
Messages
216
Reaction score
1
Location
Roseville, CA
Thank you for the assistance guys...I did a final reading on a batch or Radioactive Red and the final was 1.012 @ 70 degrees...got it figured out I think.

Thanks again!
 

Latest posts

Top