A man with two clocks...*

[olie]

Been using my glass hydrometer with great success for a couple of years when I finally got a Tilt, which I love...

...But...

It reads about .005 off from my glass one.

"A man with two hydrometers is never quite sure of his gravity."

So, the Tilt can be calibrated, in much the same way that many thermometers can, but I never really trusted "make sure it reads correctly at 0° and 100°C, then it will probably be close enough at 50°" thing. I guess I've just seen too many performance curves to trust that.

...But here I was, trusting my glass hydrometer right out of the box without even calibrating for all this time.

Anyway... I do actually have a question.

Is there some sort of "reference liquid" or something that one can use to calibrate closer to 1.060? If I tested at 1.060 and got a good reading (or calibrated to it), it would be a lot easier to trust 050 & 070. But getting a good reading (or "off by" value) at 1.000 just doesn't instill that same level of confidence.

How to reconcile?

Thanks!
~Ted

-----------
* There's an old adage: A man with one clock always knows what time it is; a man with two clocks is never quite sure.

 

[Moose_MI]

I’d like to invite people to fill in the blank...


“A man with 2 clocks.... _________________”

 

[olie]

Well, as I mentioned in my original, the old adage is "...is never really sure what time it is."

 

[Moose_MI]

...needs to put one down so he can drink a homebrew

 

[Soulshine2]

Been using my glass hydrometer with great success for a couple of years when I finally got a Tilt, which I love...

...But...

It reads about .005 off from my glass one.

"A man with two hydrometers is never quite sure of his gravity."

So, the Tilt can be calibrated, in much the same way that many thermometers can, but I never really trusted "make sure it reads correctly at 0° and 100°C, then it will probably be close enough at 50°" thing. I guess I've just seen too many performance curves to trust that.

...But here I was, trusting my glass hydrometer right out of the box without even calibrating for all this time.

Anyway... I do actually have a question.

Is there some sort of "reference liquid" or something that one can use to calibrate closer to 1.060? If I tested at 1.060 and got a good reading (or calibrated to it), it would be a lot easier to trust 050 & 070. But getting a good reading (or "off by" value) at 1.000 just doesn't instill that same level of confidence.

How to reconcile?

Thanks!
~Ted

-----------
* There's an old adage: A man with one clock always knows what time it is; a man with two clocks is never quite sure.

I would think your calibration "medium" should or would be distilled water at whatever temperature the instructions tell you. this would zero anything out . After that if you plan (insist?) on using two or more "tools" to measure, average them out to get your "accepted" reading. If it were me, pick one to excuse yourself from a headache on brew day. Is supposed to be a relaxing hobby.

 

[Soulshine2]

Well, as I mentioned in my original, the old adage is "...is never really sure what time it is."

not that I dont carry my phone like everywhere but I quit wearing a watch a few years ago. Used to be obsessed with what time it is ...then my sweet mother in law passed from a 3 yr bout with cancer. now I just try to enjoy life as it comes.

 

[Punx Clever]

Is there some sort of "reference liquid" or something that one can use to calibrate closer to 1.060? If I tested at 1.060 and got a good reading (or calibrated to it), it would be a lot easier to trust 050 & 070. But getting a good reading (or "off by" value) at 1.000 just doesn't instill that same level of confidence.

How to reconcile?

I have three tools to measure gravity. Refractometer for sparge/boil/OG, Tilt to monitor fermentation, Hydrometer to get final gravity.

The Tilt has too many variables associated with it to rely on it for precise final gravity (can't stop a clump of yeast from getting stuck to it), so I use it for trends.

I suggest you pick one to "believe" then relax, don't worry and have a homebrew. It's not like you have to keep track of it for the tax man.

Alternately, make a sugar/water solution that should be in the ballpark of 1.060. Measure the mass of 100ml of this solution. 100ml of pure water is 100g. 100ml of a solution with a SG of 1.060 will have a mass of 106 grams.

 

[S-Met]

Alternately, make a sugar/water solution that should be in the ballpark of 1.060. Measure the mass of 100ml of this solution. 100ml of pure water is 100g. 100ml of a solution with a SG of 1.060 will have a mass of 106 grams.

I think 1lb sugar in 1 gal of h2o = 1.040. I would suggest verifying that with a 3rd party as I might be confused.

Assuming the measurement is correct, 1.5lb sugar in 1 gal distilled h2o should give you a 1.060 solution. 1 gal syrup is a lot, I would 1/4 the batch, 1qt h2o, 3/8 lb sugar. Use your scale to measure sugar as accurately as possible and be very precise on your h2o volume. Bring up to 150f (approx) and stir in the sugar until disolved. Let it cool to your calibration temp, then check it with tilt and your hydrometer.

If you think in metric, this site has a good chart of s.g. in g/l - 157.5g/l=1.060
https://mpesgens.home.xs4all.nl/thwp/convtabl.html#hydro

 

[Soulshine2]

I have three tools to measure gravity. Refractometer for sparge/boil/OG, Tilt to monitor fermentation, Hydrometer to get final gravity.

The Tilt has too many variables associated with it to rely on it for precise final gravity (can't stop a clump of yeast from getting stuck to it), so I use it for trends.

I suggest you pick one to "believe" then relax, don't worry and have a homebrew. It's not like you have to keep track of it for the tax man.

Alternately, make a sugar/water solution that should be in the ballpark of 1.060. Measure the mass of 100ml of this solution. 100ml of pure water is 100g. 100ml of a solution with a SG of 1.060 will have a mass of 106 grams.

what youre suggesting would be difficult if the OP doesnt know if his hydrometer is calibrated...water (distilled I would imagine) is the calibration medium, SG is 1.000 at 60*F ,read the paper slip that should be included with each hydrometer. Making a "ballpark " solution of 1.060 if its not previously calibrated would at best , be a guess.
I do agree though that once 2 or more are used for the same function , to just take one and believe in it as the measuring tool.

 

[olie]

I have three tools to measure gravity. Refractometer for sparge/boil/OG, Tilt to monitor fermentation, Hydrometer to get final gravity.

Heh. Hijacking my own thread...

You use a different tool to measure OG than FG? Are you not concerned with differences, there?

I get the "relaxing hobby" thing, but part of the enjoyment for me is to attempt to apply a bit of rigor to the process. Sure, I can slop together some decent beer, but I rather get a kick out of "knowing" (heh) all the various stats & whatnot. (Much the same as some people like to have a beer + picnic and watch the game, while others have more fun thinking about how this next at-bat will affect the player's RBI and other stats. It's not a matter of one has to chill out or the other needs to pay attention; it's just 2 different ways of enjoying things.)

 

[olie]

I do agree though that once 2 or more are used for the same function , to just take one and believe in it as the measuring tool.

In terms of repeatability, that certainly works (so long as I don't do something to alter the tool, like crack the glass & have to buy a new one).

Again, this is more a matter of: I enjoy geeking-out on the numbers, and I enjoy it less if the numbers seems suspicious to me.

Replies of the form "change a fundamental property of your personality or don't brew beer" aren't helpful.

Back to the Q and some of the answers: So y'all seem to be saying that, once I get distilled water @60°F to read 1.000 (or have an adjustment number), that it's ok to use that same calibration for higher readings, yes?

Again, I get that some of you don't care to be so precise -- that's cool. My question is: for those folks who do care, how do y'all do it?

Thanks!
~Ted

 

[Soulshine2]

"Back to the Q and some of the answers: So y'all seem to be saying that, once I get distilled water @60°F to read 1.000 (or have an adjustment number), that it's ok to use that same calibration for higher readings, yes?"

yes, this is the method of calibration. distilled (pure,without minerals or salts) water at 60*F should calibrate it .... Ok , lets step back a little , it wont calibrate the hydrometer itself but rather if by whatever reason the reading is not 1.000 at that point then record the amount of correction (this would be your adjustment number)and correct all future readings by that same amount.

 

[Soulshine2]

The scale within the hydrometer is a simple slip of paper. If by any chance it is bumped ,dropped or shaken and miraculously it doesn't break , the paper scale could in fact slip from its position and give a false reading. This is why it is recommended to calibrate it from time to time. Otherwise , treat it very delicately.
Assuming you bought the hydrometer new and the storage tube still has the paper set of users manual /instructions and temperature correction chart...read it thoroughly.

 

[Soulshine2]

Theres no reason to use 3 separate tools when one will suffice. How do you know they're all synchronized in calibration???

 

[cyberbackpacker]

I am surprised no one has said, "really, 5 thousandths of a point difference"? I am actually pleasantly shocked by how equivalent both of your devices read.

That said, do as soulshine said in post #12, and then proceed accordingly!

 

[cactusgarrett]

Theres no reason to use 3 separate tools when one will suffice. How do you know they're all synchronized in calibration???

I generally agree, but disagree for a specific circumstance: Many people brew on the 1 gallon scale, and therefore, removing one (let alone multiple) hydrometer tubes' worth of brew seriously impacts the output volume. As a result, it's beneficial to to use a hydrometer on brew day, then a refractometer (to only pull a few drops) during fermentation and save volume.

 

[Soulshine2]

pay attention at about 1:45 mark...

Youve got it backwards . Use the refractometer BEFORE fermentation.

 

[cactusgarrett]

I'm speaking to the volume issue, not the "accuracy in the presence of alcohol" issue. If done as I suggested, a conversion would be needed once fermentation has started to accurately measure gravity in the presence of alcohol.

 

[Soulshine2]

OP stated"...But here I was, trusting my glass hydrometer right out of the box without even calibrating for all this time."

Im trying not to complicate things for the OP with refractometers , conversion charts and such.
Basics and good habits need be adhered to first.

 

[olie]

I am surprised no one has said, "really, 5 thousandths of a point difference"? I am actually pleasantly shocked by how equivalent both of your devices read.

In absolute numbers, that's what I was thinking, at first.

...But then, 1.065 ~= 1.070. In terms of gravity, that's a difference of almost 8%. For 1.015 vs 1.010, it's 30% (or 50%, if you're going the other way).

So that's kind of a lot.

 

[olie]

Btw, all the feedback thus far is very helpful. I don't mean to sound argumentative -- I'm just trying to explain where my head is/was at, in hopes that it will help others to better teach me.

So far, I'm learning a bunch.

Thanks!

 

[Brooothru]

Btw, all the feedback thus far is very helpful. I don't mean to sound argumentative -- I'm just trying to explain where my head is/was at, in hopes that it will help others to better teach me.

So far, I'm learning a bunch.

Thanks!

The evolution of a project from design to fabrication to implementation:

Measure with a micrometer, mark with a grease pencil, and cut it with an axe.

Brooo Brother

 

[Soulshine2]

The evolution of a project from design to fabrication to implementation:

Measure with a micrometer, mark with a grease pencil, and cut it with an axe.

Brooo Brother

sledge hammer to fit...
this is like the ultimate millwright mantra.

 

[Punx Clever]

what youre suggesting would be difficult if the OP doesnt know if his hydrometer is calibrated...water (distilled I would imagine) is the calibration medium, SG is 1.000 at 60*F ,read the paper slip that should be included with each hydrometer. Making a "ballpark " solution of 1.060 if its not previously calibrated would at best , be a guess.
I do agree though that once 2 or more are used for the same function , to just take one and believe in it as the measuring tool.

Reccomend re-reading my post. I described a method to precisely determine the gravity of a solution by mass and volume. getting to the 1.060 ballpark gives him a reference point near his usual expected OG's.

Heh. Hijacking my own thread...

You use a different tool to measure OG than FG? Are you not concerned with differences, there?

I get the "relaxing hobby" thing, but part of the enjoyment for me is to attempt to apply a bit of rigor to the process. Sure, I can slop together some decent beer, but I rather get a kick out of "knowing" (heh) all the various stats & whatnot. (Much the same as some people like to have a beer + picnic and watch the game, while others have more fun thinking about how this next at-bat will affect the player's RBI and other stats. It's not a matter of one has to chill out or the other needs to pay attention; it's just 2 different ways of enjoying things.)

Yup, don't want to use up wort taking an OG hydro sample... or wait for it to cool for that matter. My refractometer is "close enough" to my hydrometer for what I'm doing.

Theres no reason to use 3 separate tools when one will suffice. How do you know they're all synchronized in calibration???

Mmmhm. You have different goals than I do.

I measure a hot liquid with little waste using my refractometer. Can't do that with a hydrometer or the tilt.

I use the tilt to monitor trends during fermentation without opening the fermenter or wasting beer. Can't do that with the refracto or hydro.

I use the hydrometer to take an accurate FG reading. Can't do that with the hydro or tilt... plus the beer is drinkable at that point, so no waste.

 

[Punx Clever]

In absolute numbers, that's what I was thinking, at first.

...But then, 1.065 ~= 1.070. In terms of gravity, that's a difference of almost 8%. For 1.015 vs 1.010, it's 30% (or 50%, if you're going the other way).

So that's kind of a lot.

"Difference of almost 8%" with respect to what reference point? 1.000? But what are you really measuring when you are taking specific gravity?

If you are using a hydrometer, you are measuring how well a stick floats and correlating it to the density of the fluid. Never mind the bubbles sticking to the stick or the surface tension of the fluid skewing your observation of the scale.

If you are using a refractometer, you are measuring the angle a beam of light makes when passing through a fluid and correlating it to the density of the fluid (which is complicated when the fluid consists of more than just a single type of sugar molecule and water)

If you are using a Tilt, you are measuring the angle that a bobber floats at and correlating it to density of the fluid. Never mind differences in the battery-to-battery weight differences in CR-123's or the giant glob of yeast/krausen stuck to the side of the thing.

Really though, you are concerned with the change from OG to FG... so lets say the real OG was 1.070 and you measured 1.080. Similarly, the real FG was 1.010, and you measured 1.015.

That means you measured the beer to be 8.5% ABV (according to whatever forula you used, each with their own assumptions and margins of error).

The actual, since your measurements were off, comes out to be 7.8%.

All of a sudden, you are measuring your ABV to be 9% higher than it actually is!!!!!

So, back to my original post... if you *REALLY* want to accurately measure the density/SG of your beer, take a 100ml sample and use a scale to determine that sample's mass. Specific gravity, being compared to water, makes the math easy... for a 100ml sample:

100g -> 1.000 SG
101g -> 1.010 SG
...
106g -> 1.060 SG
...
110g -> 1.100 SG

etc.

 

[bleme]

Kind of OT here (because @S-Met already nailed it) but I always thought it was silly to calibrate my hydrometer in distilled water if I am not brewing with distilled water. If I want to know what I got out of my malt, I have to know what gravity my water was before I added the grain. Why would I care how close that is to 1.000?

 

[brick_haus]

Specific gravity (relative density) standard solutions can be found online. Try Thomas Scientific, thats where I used to get mine.

 

[Soulshine2]

Kind of OT here (because @S-Met already nailed it) but I always thought it was silly to calibrate my hydrometer in distilled water if I am not brewing with distilled water. If I want to know what I got out of my malt, I have to know what gravity my water was before I added the grain. Why would I care how close that is to 1.000?

because it is a measuring device. If you dont calibrate it to its recommended known absolute "zero" , it's quite possibly ( yes ,even minutely ) wrong. But , at least you'll know by how much to adjust .

 

[madscientist451]

I’d like to invite people to fill in the blank...


“A man with 2 clocks.... _________________”

Can never be sure if a Clock in the hand is better than a Clock in a bush....

 

[bleme]

because it is a measuring device. If you dont calibrate it to its recommended known absolute "zero" , it's quite possibly ( yes ,even minutely ) wrong. But , at least you'll know by how much to adjust .

The difference between your brewing water and your OG will tell you how much you got from your grains. If the hydrometer measures 1.000 in distilled but 1.004 in your strike water, you will always be .004 off.