hydrometers calibrations and temperatures

[shanek17]

Hey everyone, i have a hydromerter calibrated to 68 degrees and I would like a coversion chart with a bunch of different temperatures to choose from, since temperatures can greatly differ. I did find a online calculator and tried it out. but it would be nice to have a physical chart or even a formula to use for a hydrometer. everytime i find a chart its calibrated to 60 degrees


I actually just tested my hydrometer for calibration. and i used my digital thermometer and got the water temperature to 68.5 which is close enough to 68 and my hydrometer is reading 1.004-1.005! Its supposed to be at 1.00 rite?! like is it normal for hydros to be of a bit? i try to take care of it but admittingly the hydro has been banged around some. but now im wondering why its reading higher, and maybe my wines that iv been waiting to finish fermenting are done afterall...

But since i found out my new calibration temperature is 1.005 can i just use that as my hydrometers calibration temp? i will evetually get a new hydrometer but for now i got just this one.

 

[djrockinsteve]

Luc discovered that hydrometers are all over the place when it comes to accuracy. Even the manufacturers know it. I don't adjust for temp w/hydrometer.

 

[shanek17]

damn really. Thats brutal. how do they expect us to know when our stuff is done?! .. so buying a new one may do nothing. are they all poor quality or are some more accurate?

well i took more accuarte samples and realized mine is calibrated exactly at 1.006.

so i figured ill just deduct those 6 points from all my SG measurements. Im pretty sure thats all i have to do for more accurate readings. so far its making sense to me because i had one batch, for example sitting at an SG of 1.000 but if my hydro is calibrated to 1.006. i just deduct .006

so like this

SG - 1.000
- .006
= .994

so my wine that iv been waitinf to finish fermenting is looking alot better and dryer now.

 

[Deezil]

A lot of the hydrometers come with a sheet that has the basics of how to use it as well as some rough guidelines for adjusting for temp with that particular hydrometer.

Did yours?

And yeah, hydrometers are calibrated to a lot of different temperatures, and as you've noticed, even when measured at those temps - they arent always on point. It's important to know your hydrometer in particular, and how it reads. After that (like you've done), you can make more accurate measurements.

 

[JohnT]

Question: why is it important to have a hydormeter calibrated? If it is offf a little, what's the harm.

The reson I ask is that I feel the wine is not rocket fuel. If the hydormeter is fairly accurate, then it seems to me that this is ok. After all, who cares is the wine is 13.6% apv as opposed to 13.7%?

If you use a hydrometer to determine when a wine should go into a secondary fermenter, then I again question the need for a great deal of accuracy. It is not like you will be up until 4am waiting for the sg to hit a certain reading.

Please do not take offense to the above. I do not fault folks for wanting to be percise. I just say the above to put any fears to rest. IMHO, close is just fine.

johnT.

 

[GreginND]

Please do not take offense to the above. I do not fault folks for wanting to be percise. I just say the above to put any fears to rest. IMHO, close is just fine.

johnT.

Agreed. It's close enough for me.

 

[Bartman]

I agree with John T. If you ignore the kit instructions that direct you to rack at a certain SG (which I believe most folks who have made a few kits choose to ignore) and instead, ferment to dry in the primary bucket, it shouldn't make a difference. As he said, 12%, 12.5%, 13% - does it really make a difference, since you can't be certain of the precise ABV without testing post-bottling anyway? If you are making you're 100th batch, using the same type of juice, yeast and ambient conditions, and you've not had any problems before, I would argue the calibration on your hydrometer really doesn't matter.

 

[g8keeper]

+1 to everything that was said above.....yes, we are utilizing some science, sometimes without exactly knowing how and why, or that we are, in order to make wine, which is actually more of an artform in of itself....therefore PRECISION is not necessarily required....i think the adage, "close enough for government work", applies here...i think winemaking can be added to the same category as horseshoes, hand grenades, and nuclear war as the things that close only counts in....lol...

 

[DoctorCAD]

A hydrometer could be gradated in letters and still be perfectly useful for wine making. Start at "S" and when it stabilizes at "G" for 3 days, secondary. Leave alone until it reads "B". Wine is done.

Its only a relative number start to finish, not an exact number.

 

[robie]

I pretty much agree with all of the above. Your wine is finished fermenting not when it reaches a certain SG, but when the SG is below 1.000 and it hasn't changed for 3 days in a row. Even at that, it is still good to leave a wine in secondary for an extra week or so after the SG has not changed for 3 days.

 

[shanek17]

yea some good views in here for sure. i agree that some of the accuracy for what were doing does not need to be precise. like one person said this is an artform and characteristics can form from our own intuitve decisions. and even using some good ol trial and error has its place in this hobby. im not too worried abot exact alcohol % readings. As long as i have a rough idea of what it is. and that i know whether its a light wine or some heavy - one drink knock you on your *** kinda wine. hahaa

although when i want hydrometer accuracy its been important for me when finishing my wine. Like iv been checking my hydrometer and wondering why its saying my wines are at 1.002 and sitting at 1.004 for so long and im wondering if i have a stuck fermentation. but now that i know my hydrometer is calibrated not to 1.000 but to 1.006 well that makes a big difference. my wines that iv been waiting to dry out have magically dried out perfectly fine and have been sitting and waiting to be sulfited and bottled.

 

[shanek17]

but its not just accuracy i was kind of dissapointed too see my hydrometer not calibrated properly. as its confusing for a newbie like myself. but im wondering if maybe i banged it around too much and threw off the calibration. Or maybe i bought it like that. they seem kind of fragile and perhaps its kind of a luck of the draw when you buy one, you either get a good one or a bad one. iv worked in shipping and receiving warehouses and i know what happens to products before they get to the consumer, and i can say alot of things are not handled with care! So my question is, are some hydros made better quality than others? some day i will get a new one!

 

[Deezil]

To those who've mentioned its not exactly necessary to be precise, i would agree.. For the most part.

The one part where you want some precision, is when it comes to replicating that favorite wine of yours. Say you have a hydrometer, and you make a killer wine - and you took all your measurements with that hydrometer... But you never checked how far it was off from "actual".

And it breaks. So you get a new hydrometer. Guess what! It has a different calibration. So whatever you backsweetened your wine to, is a mystery unless you get lucky with bench trials.

It's not important to *always* use your adjusted SG's with every wine.. But it is important to know where your hydrometer sits in relation to 1.000.

 

[Bartman]

And it breaks. So you get a new hydrometer. Guess what! It has a different calibration. So whatever you backsweetened your wine to, is a mystery unless you get lucky with bench trials.

Ah, yes, I suppose back-sweetened wines would require use of the hydrometer again. See, my family and friends don't care for sweet wines much at all, so it's pretty much dry reds 99 out of 100 times.
(Just between you and me, there have been a few occasions with a red kit I had made several times before, where I have checked but not recorded the SG at the start, and never checked it again - it's my secret shame! )

 

[g8keeper]

well i'll normally check my sg to make sure it's finished fermentation, but then when backsweetening i have just used my tastebuds as my guide....add some, stir in, draw a sample and taste....repeat until it's to my liking....i know, i know....i should then record that level to remember for next time in order to replicate....but in my case, it's been more about making different types of wine from different juices and such, and very seldom yet have i gone to doing duplicates....just like bartman, that's my secret shame....lol...

 

[BobF]

The most accurate thing a hydrometer can tell is delta. Keep in mind that a hydrometer tells you the total amount of dissolved solids. If you use tap water to check your hydro, you aren't really standardizing it. But, it doesn't really matter +/- a few points anyway.

Why? Because the -assumption- we make when using a hydrometer is that the total reading is due to fermentable sugar. It isn't. Every must/wine is going to vary in the amount of -other- dissolved solids. You can figure anywhere from 5-10% (SWAG based on reading a jillion texts, don't ask for a cite) of the total dissolved solids to be stuff that's not fermentable sugars. And there is no way to determine what percentage is sugar using a hydrometer alone.

There are other inaccuracies such as CO2 as well ... so, the best you can hope for is a reasonable -estimate- of ABV based on the difference between SG and FG, and whether or not the ferment is either complete or stuck based on consecutive same readings.

Relax. You'll be close enough to have an idea of where your wine's ABV is relative to high/medium/low.

If you want to really nail down the alcohol content and residual sugar levels, you'll need to spend a lot of money. IMO, the money is better spent on other winemaking toys and ingredients

 

[shanek17]

The most accurate thing a hydrometer can tell is delta. Keep in mind that a hydrometer tells you the total amount of dissolved solids. If you use tap water to check your hydro, you aren't really standardizing it. But, it doesn't really matter +/- a few points anyway.

Why? Because the -assumption- we make when using a hydrometer is that the total reading is due to fermentable sugar. It isn't. Every must/wine is going to vary in the amount of -other- dissolved solids. You can figure anywhere from 5-10% (SWAG based on reading a jillion texts, don't ask for a cite) of the total dissolved solids to be stuff that's not fermentable sugars. And there is no way to determine what percentage is sugar using a hydrometer alone.

There are other inaccuracies such as CO2 as well ... so, the best you can hope for is a reasonable -estimate- of ABV based on the difference between SG and FG, and whether or not the ferment is either complete or stuck based on consecutive same readings.

Relax. You'll be close enough to have an idea of where your wine's ABV is relative to high/medium/low.

If you want to really nail down the alcohol content and residual sugar levels, you'll need to spend a lot of money. IMO, the money is better spent on other winemaking toys and ingredients

thanks bob, i actually used reverse osmosis water to standardize my hydro. why does tap water not work well? i called my LHBS and the ladie made a good point when i asked her about calibrating my hydro. she said she wasnt sure if my hydro is calibrated at 68 degrees in water or a dry wine.

yea it sounds like accuracy comes with alot of expensive equipment and i agree id rather buy some more toys and ingriedients!

 

[BobF]

RO water should give you a good read. Tap water is generally high in dissolved minerals, so not good for this kind of measurement.

 

[ibglowin]

Distilled is still the gold standard for calibrating Hydrometers. RO water is not the same as Distilled. That said it is doubtful you would see much difference between the two reading wise with a $5 tool.

 

[Ernest T Bass]

Kinda off the subject, but, I checked my well water with my new pH Meter, after calibrating it with 4.1 and 7.1 buffer solution and it has a
pH of 5.6. I was expecting somewhere around 7.0. Any thoughts?
Semper Fi