Check Your Refractometer Calibration!

[3 Dawg Night]

My last two brews had taken a nosedive on efficiency, or so I thought. This afternoon, on a whim, I decided to check my refractometer calibration with distilled water. It reading low by ~1.5P! After resetting the zero point, my gravities and efficiencies are back up where I expected them to be.

The lesson here, boys and girls, is to check your refractometer's calibration every time you use it!

 

[bracconiere]

i'm still a refractometer virgin.....stories like this scare me off. if i thought i was off on my OG, getting bad effec. i'd end up being sad and getting fat! i'd be off on how many calories it had! lol

 

[3 Dawg Night]

i'm still a refractometer virgin.....stories like this scare me off. if i thought i was off on my OG, getting bad effec. i'd end up being sad and getting fat! i'd be off on how many calories it had! lol

Calibration is really not hard at all; I'm just lazy. You just put a few drops of water on the lens and turn the adjustment screw to get 0 Plato/Brix. It's so much easier to use than a hydrometer!

 

[bracconiere]

Calibration is really not hard at all; I'm just lazy. You just put a few drops of water on the lens and turn the adjustment screw to get 0 Plato/Brix. It's so much easier to use than a hydrometer!

yeah, and i've seen them for $15 or so also....i've got two vintometers, not like i ever use them though. maybe i'll take the plunge some day! .

 

[LarMoeCur]

I bought one after breaking a hydrometer many years ago. They are so easy to use, I'd never go back. If your brewing all grain, i can not see not having one. Cooling a sample three or for times a brew day is such a waste of time.

 

[Barbarossa]

Ah, distilled water is probably what was missing for me, because when I calibrated it with tap water, the wort reading was five points over than with my hydrometer.

 

[jrgtr42]

I must be pretty lucky - when calibrated using my tap water, my readings on the refractometer match my hydrometer to within a point or 2. Close enough for government work for me. Same with the calculator at the end - without changing the correction factor from 1.0, it's a similar result.
|Honestly, I usually don't usually even use the hydrometer much any more - maybe I'll do a backup reading every few brews to make sure everything's on the level.
|I do want to start messing with my water, grab a decent but inexpensive RO water machine and start building profiles from scratch to match the style. I just have to convince my dad to go halvsies on it to use for his tropical fish - the water where he is goes nuts day to day for it.

 

[TrainSafe]

So, I have a batch of wine going, from a kit. For the life of me I couldn't figure out why the primary fermentation was stuck. I had a vigourous start, but then it stalled at 1.020 after a couple weeks. I added a heat pad under the wine, and added some yeast energizer. Four days later the wine was at exactly the same spot. I grabbed a hydrometer and discovered it was done (0.996) but my refractometer was off.

Today I tested it on a mexican lager I have fermenting. Refractometer says 1.040 while the hydrometer (2 of them) say 1.018-10.20.

Guess it is time to figure out how to calibrate this thing.

<off to find the documentation>

 

[TrainSafe]

Looks like calibration is super easy.

 

[NSMikeD]

Any time my numbers are off, the first two places I look are uncalibrated measuring instruments and the user.

 

[3 Dawg Night]

Looks like calibration is super easy.

Mine is just a tiny adjustment screw. Since I started checking my calibration every time, I've been amazed how much it's off every time, even after a few days (or even on the same day)!

 

[mcmeador]

I always do my brew day gravity readings with both a refractometer and a hydrometer. It always makes me feel better to confirm one with the other.

 

[jrgtr42]

So, I have a batch of wine going, from a kit. For the life of me I couldn't figure out why the primary fermentation was stuck. I had a vigourous start, but then it stalled at 1.020 after a couple weeks. I added a heat pad under the wine, and added some yeast energizer. Four days later the wine was at exactly the same spot. I grabbed a hydrometer and discovered it was done (0.996) but my refractometer was off.

Today I tested it on a mexican lager I have fermenting. Refractometer says 1.040 while the hydrometer (2 of them) say 1.018-10.20.

Guess it is time to figure out how to calibrate this thing.

<off to find the documentation>

presuming the OG was where it was supposed to be -
It's probably not calibration that's the issue - it's the fact that refractometers don't read accurately in the presense of alcohol.
|The good news is there's a calculator available (several, in fact.) I use the one on Brewers Friend Refractometer Calculator.
Technically there's a method for a correction factor, but with the OG in Brix, and the currect reading in Brix, it's close enough for government work. Occasionally I'll even just use the number as it is to make sure the gravity is stable.
|It's not a bad idea to back up readings with the hydrometer just to make sure as you get used to it.