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My refractometer just arrived...now what?

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OK. It measures gravity in Brix. So the first thing you need is to convert Brix into Specific Gravity. Go to: http://www.fermsoft.com/gravbrix.php
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Place a couple of drops of cooled wort on the site glass and read the meter using a natural light source. After you get an accurate reading use the table to get gravity. That's about it.
 
I have a vial of distilled water I keep with mine as well as the mini-droppers. Calibrate to zero using a drop or two of the distilled water before each use.
 
Very simply, grab a sample with a pipette and shake the bulb a little in a cup of cold water just to knock off some of the heat (assuming it's near boiling). Drop a bit on the glass, close the cover and look into it. Note the BRIX and multiply by 4 and subtract 1 (driveway-good-enough method). Wipe the sample off with a damp papertowel but do NOT dunk the instrument into water to clean. Bad bad idea. I know.
 
After you calibrate with distilled water at the proper temp, take a few readings and measure against a hydrometer to see how accurate it might be. I have found mine to be pretty accurate so far, but I've heard of others who have not been so accurate over a range of readings.
 
It's also a good idea to take several readings. Since the sample is so small, any air bubbles or break/hop material can throw off the reading.

I only use the refractometer for OG readings. I found the various spreadsheets/formulas for calculating FG to be too inaccurate to be of much use to me (+/- 0.005 SG).
 
. . . . . .I only use the refractometer for OG readings. I found the various spreadsheets/formulas for calculating FG to be too inaccurate to be of much use to me (+/- 0.005 SG).

+1, I don't use it at all for anything that has fermented. Ye olde hydrometer reigns supreme after fermentation:mug:
 
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