Refractometer question

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Scaggs

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I recently bought a refractometer and it's giving confusing results. I tested a beer, which had a starting gravity of 1.060, with my hydrometer. I was reading the hydrometer before bottling as about 1.015 which gave me an ABV of 5.91%

My refractometer has both Brix scale and SG Wort reading. The SG is reading as 1.030 wich only gives me ABV of 3.4%. But if I use the Brix scale - 8, I get the same reading as my hydrometer.

Not sure if I'm doing something wrong or the SG scale on the refractometer is way out.

Has anyone had similar problem?
 
Hi Bigcol,
I did use the calculater on brewers friend but not sure if it takes into account the wort correction factor. Going to have to do some reading on the subject I think
 
In summary, don't use the SG scale on the refractometer, use the BRIX scale and the Brewers Friend conversion calculator: https://www.brewersfriend.com/refractometer-calculator/ (section II has the FG calculator built in). As Bigcol49 says, you can get into a long process of setting the wort correction factor, but on all the readings I've checked with a hydrometer the results have been close enough for me not to want to bother! Personally I'm happy to sacrifice a little bit of accuracy for the convenience of the refractometer and the small quantity of wort required for the test. For judging the end of fermentation I think it's brilliant.

My only issue is that the blue line is sometimes hard to see, and maybe Father Christmas will bring me an electronic digital refractometer :-)
 
People who buy refractometers with "SG" scales soon learn that they've been hood-winked by the manufacturer or seller! Refractometers do not do "SG" - that's for hydrometers. But the native scale (no doubt BRIX) can be easily converted to SG with a simple calculation (online calculator, etc) that will take into account alcohol content (or whatever else, but alcohol is the important one for us).

@BassoonBrew covers it well. And mentions the trouble seeing the "blue line": A refractometer is an optical tool, when the beer is full of yeast the light is scattered so the line becomes unclear (but clear enough to make a decent judgement). When it really matters, at the beginning and at bottling/kegging time the beer is relatively free of crud and the line is sharp. I think there are changes with type of beer (light or dark) that you can compensate for but hardly makes a difference worth bothering with.
 
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