hydrometer accuracy

[johnluc]

Hi all, having had no end of problems with stuck brews (1018) for every brew i've done for at least the last 10 i have tried every thing from different yeasts to making a stir plate and using liquid yeasts, my last brew was the same and starting to p*ss me off, found an old hydrometer and tested and found that it was virtually bang on, now for the last two years i've been using two identical hydros,both read 1000 using water and both read the same FG, my old cheapo one also reads 1000 in water but read at least 4 points lower on FG,is there any way i can check the accuracy of any/all of my hydrometers,
cheers, johnluc.

ps i'm using a temp controlled fridge so it's not a temp problem.

[Aleman]

10g of sugar in 90g of water should read 1.040 . . . its 10% Brix as well

[johnluc]

thank you Tony, will try that.

[johnluc]

10g of sugar in 90g of water should read 1.040 . . . its 10% Brix as well

just tested and both my identical ones are both reading 1044, out a bit but not significant enough for my stuck brews, now totally p**sed off don't know what else to try.

[Rick_UK]

Assume you have checked your mash thermometer too? If it's out and your mashing a few degrees warmer that would explain it.

Rick

[johnluc]

Thanks for your reply Rick, yes one of the first things i did was to replace my thermometer when it started, bought an ETI digital, really don't know what else to try, really frustrating, although the beer is pretty good i think it could be better.
johnluc

[Aleman]

May sound a radical approach but have you considered a refractometer? I'd trust one of those to read 'standard' solutions of sucrose to calibrate a hydrometer against.

The other possibility is a narrow range hydrometer from say hamsted homebrew. They do a 1.0000 to 1.0500 for around a tenner plus postage. I use that one with the refractometer for fermenting wort to determine the correction factor for the calculations for brix to gravity for different wort types.

[Capped]

10g of sugar in 90g of water should read 1.040 . . . its 10% Brix as well

Cue everyone (well, me anyway) rushing off to check. Both of my ancient ones are spot on!

[roscoe]

these narrow range hydrometers are the dogs,.... brill

(however, they are uber fragile and should come with a box of kleenex for the tears !)

just wish they were cheaper...

May sound a radical approach but have you considered a refractometer? I'd trust one of those to read 'standard' solutions of sucrose to calibrate a hydrometer against.

The other possibility is a narrow range hydrometer from say hamsted homebrew. They do a 1.0000 to 1.0500 for around a tenner plus postage. I use that one with the refractometer for fermenting wort to determine the correction factor for the calculations for brix to gravity for different wort types.

[johnluc]

thanks for your replies guys, will buy a new hydrometer and think will certainlly think about a refractometer, can anyone tell me if the cheaper ones from ebay are worth buying. or any recomendations would be much appreciated.
johnluc.

[MTW]

An interesting thread!

I own a 0.985-1.020 finishing hydrometer (from Hop and Grape) but only a standard HB job for above that. I did Aleman's test above, weighing very carefully on scales I have checked with known weights. My bog standard hydrometer read 1.047, even though it reads 1.000 in water. Hmm.

I then diluted that test sample 50/50 with water and it read around 1.023. I splashed in a little more water to get it into the range of my finishing hydrometer. They were about a degree off at that point, with the basic model reading 1.016 when the finishing hydrometer rad 1.015. In tap water, they both read 1.000.

I have a refractometer on order which will be interesting to compare. I also plan to do some more diluted comparisons, though it looks like the possible inaccuracy of my general hydrometer may be worse the higher the gravity. Possibly...

The idea that my OGs could be that far off will certainly see me putting an expensive hydrometer on my xmas list if the refractometer backs it up!

[Dave S]

thanks for your replies guys, will buy a new hydrometer and think will certainlly think about a refractometer, can anyone tell me if the cheaper ones from ebay are worth buying. or any recomendations would be much appreciated.
johnluc.

Jim was pondering one here and eventually went for one from Amazon - about £22 - not bad, seems to come recommended. Might put one on my Xmas wishlist, not that I feel I need one particularly, but with the problems people seem to be having with their hydros, it might be useful to have one.

[johnluc]

ok guys just spent the best part of an hour going through numerous posts on refractometers, now considering my original problem i read that they're not much good for reading FG. any thoughts?
johnluc.

[Dave S]

ok guys just spent the best part of an hour going through numerous posts on refractometers, now considering my original problem i read that they're not much good for reading FG. any thoughts?
johnluc.

I've heard that too, though I've never used one so can't say. Aleman will know.

[MTW]

The finishing hydrometer is probably the tool for FG. I've ordered the Amazon refractometer Jim was referred to on the other thread, which will be useful for unfermented wort.