Yet another complaint thread about a malfuntioning refractometer!!!

[bing09]

I gave in and bought a refractometer on amazon for $40. I decided to switch to a refractometer because I now do small batches (2-3 gal) and didn't want to waste a portion of the brew to take. Hydrometer reading. With that being said, I brewed today and used my new refractometer for the first time. My readings after my mash with the refractometer was at 1.042 with the promash conversion. I thought this was low so I used a hydrometer too and it came in at 1.046 which is right where it was supposed to be. I then did the boil and after boil my refractometer said only 1.048. This was way off as my post boil SG was supposed to be 1.054. I didn't compare this to my hydrometer bc I didn't feel like sanitizing it. After all that I guess does anyone know why my refractometer is reading so low and do others have his problem as well? Thanks in advance!!!

 

[wyzazz]

Did you calibrate it?

 

[Revvy]

Did you calibrate it?

The only complaint threads I've come across about refractometers on here turn out to be operator error issues, like folks not calibrating them properly, trying to read already fermented beers with it where the alcohol content throws it off, stuff like that. I've not come actoss any complaint threads where there was actually something wrong with the refractometer, just the brewer using it wrong.

 

[DakotaPrerunner]

We are also working under the impression that your Ebay refractometer reads in brix. Some are designed to be used for antifreeze or salt water aquariums.

 

[HItransplant]

I dont have a refractometer, but Im not really sure how you can determine that your equipment isnt working. The fact that your reading doesnt match what the OG was "supposed to be," doesnt really tell you anything.

 

[ClaudiusB]

for the first time. My readings after my mash with the refractometer was at 1.042 with the promash conversion.

Before you can use a refractometer correctly two things need to be done, calibration and determine the Brix correction factor.
Determining the Brix correction factor is a one time deal and you enter the correction factor into ProMash system settings.
A Brix refractometer calibration is based on sucrose not wort (Maltose, etc.) and for this reason it is necessary to use a correction factor.

For more information take a look at ProMash calibration section.


Cheers,
ClaudiusB

 

[bing09]

Yes I calibrated it to water but did not calibrate it for the correction factor. I was thinking it wasn't workin properly bc it was four points lower than my hydrometer reading. Does debris in the sample cause the refractometer to read differently bc I noticed most of my drops of sample did have a little bit of debris in it. And yes this refractometer is supposed to be used on beer and not salinity or antifreeze.

 

[Bentpirate]

You want the sample debris free for a more accurate read.

 

[bing09]

You want the sample debris free for a more accurate read.

Any suggestions on how to not get debris in there because that seems pretty hard to do wig all the hops and everything else.

 

[rcrabb22]

What was temperature of your refractometer? If you were brewing outside and it got cold it could throw off the readings.

Does your refractometer have Automatic Temperature Compensation or ATC?

Keep in mind ATC corrects for the environment the refractometer is subjected to, not for the sample. The scale in the refractometer "floats" on a bi-metal wire, same principle as bi-metal thermometers. It is a narrow correction range however so I always leave my refractometer in the house in both hot and cold weather extremes of the current season. This information came from the Basic Brewing podcast dated Sept. 2, 2010 (visit www.basicbrewing.com to listen)

The hot wort sample is no more than 1/2 teaspoon or so and quickly cools on the refractometer lens. It should not be an issue.

 

[Revvy]

Water or Distilled water? My understanding has always been that you need to calibrate with distilled...I'm not sure how much of a difference it makes, BUT if you are off a couple points, and calibrate with water that reads a couple points different, then that could be your problem.

So what are you using to pull your drops? Did it come with a tiny pipette? I can't see how any particulates could into that little openning. I've never had particulate matter in any of my samples.

 

[wyzazz]

I've never gotten any particulate in any of my samples either, I take a spoonful during the boil and blow on it, then drop it on the refractometer. For samples during fermentaton I use the pipettes. No air bubbles, no particulate or it will change the reading.

 

[bing09]

Yes it was calibrated with regular tap water, but I don't understand how there is a difference between tap and distiller water because neither one should have any sugar in them. Yes my refractometer has an ATC. Also I used a pipette but when u put the few drops on the glass...you can see there were a few bits of particulate matter.... probably hop material. I'm still confused.

 

[wyzazz]

Your tap water may have minerals, etc in it that can throw off the reading.

 

[bing09]

Mineral affect density which reflects the wavelength???

 

[wyzazz]

I don't know the science behind it but mine says to calibrate with distilled water. And I do know that my tap water reads differently than distilled.

 

[bing09]

Ok I will calibrate to distiller water and see if that helps

 

[Revvy]

I don't know the science behind it but mine says to calibrate with distilled water. And I do know that my tap water reads differently than distilled.

I've seen postings on here where the descrepincy between distilled and their tap water was 4-6 gav points....which is about what the OP's readings are off by.

Ok I will calibrate to distiller water and see if that helps

What was it we were saying about operator error vs malfunctioning refractometers threads?

 

[bing09]

Well if thats the case this thread should be obsolete very soon! Ha I will try and recalibrate it tomorrow and see how that goes. The only bad thing is that I probably won't be brewing for a few months so I won't be able to see if it's accurate for awhile....but that you for all of the positive (maybe?) criticism and advice..

 

[Revvy]

Well if thats the case this thread should be obsolete very soon! Ha I will try and recalibrate it tomorrow and see how that goes. The only bad thing is that I probably won't be brewing for a few months so I won't be able to see if it's accurate for awhile....but that you for all of the positive (maybe?) criticism and advice..

I keep a test tube of distilled water in the case with the refractomter. It's a good idea to calibrate before every use.

I was only giving you a hard time because you said this is ANOTHER malfunctioning refractometer thread, like there's some epidemic out there, and honestly there's NEVER been a malfunctioning refractometer thread on here, that I've seen. It may appear if you look at the titles, but the reality is, that, just like this tread, the user wasn't doing something right, like not calibrating with distilled.

It's not too different from new brewer's starting a thread titled, "Another infection thread" in reality those too turn out to be false alarms, mostly new brewer panic threads." If you look at the titles you think every other batch is infected, when in reality that too is a rarity.

 

[bing09]

No worries...

 

[ClaudiusB]

Ok I will calibrate to distiller water and see if that helps

Don't forget to determine the Brix correction factor or ProMash will give the wrong conversion.

Catt22 and I must be lucky our Refractometers gives us the same reading with or without distilled water.

Cheers,
ClaudiusB

 

[Catt22]

Your tap water would have to be majorly phuked up to register a reading on a refractometer and if it did so, I would look to finding another source of brewing water.

 

[iaefebs]

Your tap water would have to be majorly phuked up to register a reading on a refractometer and if it did so, I would look to finding another source of brewing water.

I was thinking the same thing. I don't see any difference between tap and distilled but since the wife uses distilled for the steam cleaner I use that when calibrating.

 

[Catt22]

I was thinking the same thing. I don't see any difference between tap and distilled but since the wife uses distilled for the steam cleaner I use that when calibrating.

You certainly can't go wrong using distilled water and I nearly always have some around the house for various other uses. After checking a few times with both tap water and distilled, I've found that there is no discernible difference. I don't think that tap water which registered a reading on a refractometer would meet the federal regulations.

 

[bing09]

You certainly can't go wrong using distilled water and I nearly always have some around the house for various other uses. After checking a few times with both tap water and distilled, I've found that there is no discernible difference. I don't think that tap water which registered a reading on a refractometer would meet the federal regulations.

So if u didn't see any difference when calibrating then why use distiller water....?

 

[Catt22]

So if u didn't see any difference when calibrating then why use distiller water....?

I don't.

 

[ajf]

There's two other things to consider.
1. Have you calibrated your hydrometer? Perhaps your hydrometer could be inaccurate. I know most of mine were.
2. What temperature did you take the hydrometer reading at? Temperature compensation for hydrometer readings can be very inaccurate with more than about 30F difference between the calibration and sample temperature.
FWIW, I found that the default brix correction factor of 1.04 in Promash gave me good accuracy when brewing pale ales.

-a.

 

[bing09]

Water or Distilled water? My understanding has always been that you need to calibrate with distilled...I'm not sure how much of a difference it makes, BUT if you are off a couple points, and calibrate with water that reads a couple points different, then that could be your problem.

So what are you using to pull your drops? Did it come with a tiny pipette? I can't see how any particulates could into that little openning. I've never had particulate matter in any of my samples.

I used distilled water and it read zero as well so I am not convinced by all the comments that distilled water must be used.

 

[Orthobrewsky]

I used distilled water and it read zero as well so I am not convinced by all the comments that distilled water must be used.

I can't see why distilled water would be preferable unless one is in the habit of using distilled water in beer. It seems we'd want our beer water to read zero before the beer is there.