Refractrometer is killing me!!!

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alz28

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Decided to do my first Stout this past Sunday a Southern Star Burried Hatchet Clone. During my boil I was checking my gravity trying to boil down to a 1.088. Well to make a long story short I boiled down to a 1.089 and started to chill my wort. After all chilling I ended up with a 1.079. I noticed that it was also hapening with my Witt beer. When I check it durring boil it shows higher gravity and lower gravity after chilling. I know I must be doing somthing wrong. I give time for the wort sample to cool even though its only a few drops. The way I am taking samples durring the boil is by taking a spoon and taking a sample off the top of the boil kettel as well as sticking the end of the refractrometer in the wort. When I stick the refractrometer in the wort I give it a while longer to cool because the body of the refractrometer is holding alot of heat. Durring to boil process I noticed its hard not to get trub in the taken sample as well. Tell me what Im doing wrong? Thanks Fellas.
 

Rockape66

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My 2 cents, but maybe the water is evaporating off your hot sample bfore you actually take your reading giving you a false high gravity. I would cool a sample to whatever temp your refractometer is calibrated at before taking a reading. You might have instructions with your refractometer for temp correction. Good luck.:mug:
 

carrotmalt

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I don't think you should be dipping the meter directly into the hot liquid.

I stir it well first, then take a very small sample with the pippet that came with my refractometer. I'm only pulling a few drops, so it cools pretty quickly before testing it. After a minute or 2, I put 2 or 3 drops on the refrac and put the cover down. Tap it a few times to make sure there aren't any bubbles. Then wait a minute or so and read (I think my instructions say to wait 30 seconds). So far this has worked for me pretty well. Good luck.
 

ThatGuyRyan

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Yea don’t stick it into the boil or wort since that just can’t be good for the refractor. I usually pull about an ounce of wort and put it in a bowl in the freezer for a few minutes and then check. Every now and then I pull enough off to use my hydrometer also and compare the two and the two have always been in check. I would say that the issue is that sample and or refractor is just too hot causing the false readings. Have you also adjusted the refractor using distilled water?
 

Montanaandy

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I don't think you should be dipping the meter directly into the hot liquid.

No kidding. Um, unless you have a refrac that I am not familiar with, you normally use an eye dropper to pull a sample (3-4 drops) that are placed on the refract glass to take a reading. Perhaps I am missing something here...
 
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alz28

alz28

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I don't think you should be dipping the meter directly into the hot liquid.

No kidding. Um, unless you have a refrac that I am not familiar with, you normally use an eye dropper to pull a sample (3-4 drops) that are placed on the refract glass to take a reading. Perhaps I am missing something here...
Yea I see what your saying. Its just a satndard refractrometer nothing special about it. I just got the idea of dipping the refractrometer in the wort from a micro brewer that was having a home brewer day demonstration. Maby he had a special refractrometer.LOL
 

RiverCityBrewer

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At first I had consistency issues with mine as well but I have had good luck with it now that I follow the same set of procedures.

First and foremost, make sure you have a valid wort correction factor... its not a complicated procedure and there are many spreadsheets and software out there to calculate it for you. If this is wrong then all of your readings will be off.

Before every brew day I recalibrate the device with distilled water... this makes sure I have an accurate 0 and the glass and lid are clear and clean.

ATC on a refractrometer does not mean it corrects for the temperature of the sample, it means it corrects for the temperature of the device. This means that for the reading to be accurate, the temperature of the device needs to be inside the ATC range (consult your manual). Leaving it in direct sunlight or out in the cold will throw off the reading, keep it inside at room temperature until you are ready to use it.

To take a consistent sample I do 2 things: First I stir the wort (even if its boiling) and immediately take a 2ml sample with a pipette. Let the pipette cool for 2 minutes then place the sample on the glass.

Try and use the same light source for your readings that day. If I start with direct sunlight, I take all my readings that way. If I take a reading in sunlight and then check it against florescent light it seems a slight bit different... could just be me but I like to stay consistent.

You may have inadvertently damaged your device by dipping it into the boiling wort, so to be sure I would calculate your wort correction factor and verify your readings with an accurate hydrometer a few times before you trust only the refractrometer.

Good luck
 
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