Any way to calibrate a refractometer?

My refractometer usually gives me a reading that is a bit higher than my hydrometer. Unfortunately, at 1.000, they are identical, and the higher in gravity, the further the difference. It maxes out at about .007, which isn't a huge deal, but it would really help with my brew day calculations if there was a way to calibrate the thing.

Look on the top of the tube part of the refractometer just behind the lens area.

Mine has a little knob there covered with a vinyl cap. Remove the cap, there is a screw there. Mine came with a small screwdriver. I bought distilled water to calibrate it with.

Distilled water and a little twist of the screw and back to 0.000.

should be adjustable

IME, the cheaper refractometers are not nearly as accurate as the ones that are not cheap. My first one has both Brix and SG on it. I've found that the scales are not in true alignment. I was using SG for the readings, but when I convert to Brix, they don't match. I've since picked up a pair of new refractometers that are very accurate. Not cheap mind you (each being about 3x the cost of the first one) but much better.

If you really care about the degree that it's off at the higher gravity range, then get something that will be accurate across the entire range.

Also, the ones I have no don't use a screw for the adjustment. They have a ring that you turn to adjust. No more needing to remove a cap and use a screwdriver to adjust. These also feel significantly more solid compared with my first one.

ghank15 said:

My refractometer usually gives me a reading that is a bit higher than my hydrometer. Unfortunately, at 1.000, they are identical, and the higher in gravity, the further the difference. It maxes out at about .007, which isn't a huge deal, but it would really help with my brew day calculations if there was a way to calibrate the thing.

Click to expand...

Are you reading the SG scale directly on the refractometer, or using the Brix scale and converting?

There are a lot of refractometers out there with bogus SG scales, while their Brix scales are actually pretty accurate. I have one of those, so I only use the Brix readings, and if I'm sweating the conversion accuracy I'll plug that into a conversion program (eg: the Refractometer Tool in BrewSmith2, or the one in BrewAide on my phone if I'm not near my computer)...

Cheers!