Author Topic: Refractometer calibration  (Read 3012 times)

Offline GY brewer

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Refractometer calibration
« on: June 14, 2017, 03:44:51 AM »
I'm trying to calibrate my cheap refractometer using the beersmith2 tool. I have done 4 different SG readings/refractometer and have 4 different Brix correction factors? All at or close to 20 degrees Celsius. Refractor is calibrated to 0 with distilled water. These are my results:
4.99 Brix, 1.025 SG = 0.78992 factor
10, 1.041 = 0.98032
4.8, 1.018 = 1.04813
11.7, 1.039 = 1.20347

Anyone know why I'm getting such variable correction factors?

Offline Oginme

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Re: Refractometer calibration
« Reply #1 on: June 14, 2017, 05:27:16 AM »
With a refractometer, you are relying upon a couple of drops to represent the entire pot of wort.  You first need to make sure that your wort is well mixed.  I take at least three readings, stirring the wort and wiping the refractometer clean between each, to make sure that I achieved a good sample.  The plus with the refractometer is that you don't need to take a large sample and cool it down.  You can take a couple of drops and by the time you get to reading it, the sample is at or near room temp.  I always start by making sure the refractometer reads zero with distilled water before hand.

I use my refractometer for readings during the brew session and then take my OG reading with both the refractometer and hydrometer so that confirms the calibration of the refractometer. 
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