Hydrometers.... what is actually good?

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DVCNick

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So I recently joined the broken hydrometer club.:bravo:

I guess it was just a matter of time. I've had the same one since I started brewing and always got numbers from it that were expected. It also happens to match my new Tilt perfectly so I think both of those are pretty good.

I ordered a couple new cheap ones off Amazon. I don't think either one is accurate as they read <1.000 in water and way less than 1.000 in the light Brut ale I kegged yesterday.
They are also calibrated for 60F (supposedly) which is a pain since it is so far below room temp in my house.

Is there a known good/consistent/accurate brand out there?
Should I just try to find the temp that actually gives good readings with these cheap ones?
Other?
 
I have two of the cheap ones. One came with the NB starter kit I began brewing with 10 years ago. I bought the other at the LHBS a few years ago because I figured it was only a matter of time before the only one would break. I’m sure it would have by now if I didn’t have a spare.

Both of mine are calibrated at 60°. Since I brew in my basement that’s not a problem. Both read 000.0 in distilled water and both agree when testing the same sample. I suppose I‘m in the “if it ain’t broke, don’t fix it” camp.
 
Unfortunately, mine is broke though.
I'm going to do some experimenting with temperature before chucking them.
 
I ordered a couple new cheap ones off Amazon. I don't think either one is accurate as they read <1.000 in water and way less than 1.000 in the light Brut ale I kegged yesterday.
They are also calibrated for 60F (supposedly) which is a pain since it is so far below room temp in my house.

You should adjust your reading for your ambient temperature. Your hydrometer is calibrated for 15°C and your ambient temperature is around 20°C.
If your sample is at 20 °C, you read the measure of your hydrometer and add 1 density point.
That will be the decently precise measure.

If your hydrometer reads water at 0,999 then it should be precise.
 
It's unnecessary, but I completely love a final gravity hydrometer, as it reads in increments of 0.001 and is very well spaced out. Obviously I still need to maintain a more traditional one for readings >1.020.
This is really worthwhile if you bottle - much more reliable than a standard hydrometer for determining whether gravity is stable. Good for preventing bottle bombs. Mine is similar, but reads to nearest 0.0005 SG.
 
I've considered getting a "finishing" hydrometer, but I'm not sure... I got a triple scale from my LHBS and it has been good to me and the only time it is out of its storage tube is when it's in use. Broken glass sucks, broken hydrometers suck even more. I've wanted to get another standard hydrometer just for the sake of having a spare, because we all know what happens when you don't have a spare.
 
I got a set from Brewing America for Christmas. Theirs has a thermometer and correction scale built in which is very convenient. It reads dead on in distilled water.

I added their mash hydrometer to my set and was a little less successful. After getting weird results 2 brew days I decided to check calibration and discovered that its calibration is off 3 points. When I contacted them they immediately sent another, no questions asked. I just got it late last week and haven't had a chance to test it out. I also need to figure out how to use it. Its calibrated at 155 but I was surprised how much a sample cools by the time I poured it into the room temp test jar and add the room temp hydrometer--probably drops upwards of 30-35 degrees.
 
After getting weird results 2 brew days I decided to check calibration and discovered that its calibration is off 3 points.

You can re-calibrate it. Prepare a mixture with 100g sugar brought to 1 litre total solution volume.
That should have a relative density of 1,0382 which is pretty nice an average value for a hydrometer calibration (just aim for 38 basis points).

Now, put your uncalibrated hydrometer into the cylinder which you filled with this syrup.

If the reading is too low (the hydrometer is too heavy and sinks too much) you can try to file, gently and carefully, the base of the hydrometer. I have never done that. That's glass after all. It should be file-able. Do a little bit, measure, repeat until you strike the exact density. Don't break the hydrometer or it will become very imprecise :)

If the reading is too high (the hydrometer is not heavy enough and doesn't sink enough) then you can add some weight on it, a suggestion I read on the internet is applying some transparent nail varnish on the top of the instrument. That should add that little tiny bit of weight without increasing the volume of the instrument (thus making it sink a little more).

I never tried that I only read this on some internet page but I think it's interesting.

I will calibrate my hydrometer one day.
 
Good information. Since they replaced it I have nothing to lose trying for future reference. I did check out the new one tonight and its also dead on at 155.
 
You should adjust your reading for your ambient temperature. Your hydrometer is calibrated for 15°C and your ambient temperature is around 20°C.
If your sample is at 20 °C, you read the measure of your hydrometer and add 1 density point.
That will be the decently precise measure.

If your hydrometer reads water at 0,999 then it should be precise.

I dropped the sample to 60 prior to checking.

The Williams one is much better.... still calibrated for 60, but reads very close to .000 in my soft tap water. I'll have to get some real distilled water for a final check.
 
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