I hate my cheap refractometer

[philipCT]

Tough brew day Sunday. Stepped up grain bill on an APA I've brewed before so I could sparge a little less deeply but still hit my numbers. The readings I was getting on the refract were whack. I ended up trusting them and added a gallon of water before the boil. Mistake! This turned out to be too much and undershot my OG by 5 points (1.052 v. 1.057).

Today I read just about every thread here and elsewhere about refractometers. I have good brewday notes and looking back over them I finally figured out the readings are all within 0.5 - 0.7 Brix and that is just not accurate enough for basing gametime decisions like wort dilution or additional boil time.

I have a cheap $60 meter from one of the online houses. It seems to be okay, but I seem to frequently get 3 different readings from 3 different samples and I have to just average them and hope for the best. Bugs the living crap outta me.

Believe me I calibrate every brewday (simple to do - and seldom actually needs any adjustment) and I cool all samples adequately and I brew inside so I'm not operating outside of ATC capability and I stir and mix wort before sampling so stratification in the BK is not the issue. It's boiled down [pun intended] to the basic inaccuracy of the thing.

I may just be a spoiled brat and spend to go digital. I'm just sick of bad brewday data.

Doesn't that level of inaccuracy bother anyone else???

 

[55x11]

Tough brew day Sunday. Stepped up grain bill on an APA I've brewed before so I could sparge a little less deeply but still hit my numbers. The readings I was getting on the refract were whack. I ended up trusting them and added a gallon of water before the boil. Mistake! This turned out to be too much and undershot my OG by 5 points (1.052 v. 1.057).

Today I read just about every thread here and elsewhere about refractometers. I have good brewday notes and looking back over them I finally figured out the readings are all within 0.5 - 0.7 Brix and that is just not accurate enough for basing gametime decisions like wort dilution or additional boil time.

I have a cheap $60 meter from one of the online houses. It seems to be okay, but I seem to frequently get 3 different readings from 3 different samples and I have to just average them and hope for the best. Bugs the living crap outta me.

Believe me I calibrate every brewday (simple to do - and seldom actually needs any adjustment) and I cool all samples adequately and I brew inside so I'm not operating outside of ATC capability and I stir and mix wort before sampling so stratification in the BK is not the issue. It's boiled down [pun intended] to the basic inaccuracy of the thing.

I may just be a spoiled brat and spend to go digital. I'm just sick of bad brewday data.

Doesn't that level of inaccuracy bother anyone else???

I have a $27 refractometer. $29.99 now. Works just fine.
I cross check with hydrometer once in a while and it checks out just fine.
I like refractometer for OG, but finishing gravity hydrometer for FG.

http://www.amazon.com/dp/B00AOCKWMU/?tag=skimlinks_replacement-20

 

[GrainToGlass]

During the boil I used to cool samples on a spoon before dripping it on the refractometer. I was getting inconsistent and high readings. Now I understand that you should get hot samples onto the refractometer and close the plate asap before the water vapor escapes. Give the refractometer a couple seconds and it should be an accurate reading. Is this the problem you're having?

My refractometer was $30 with ATC. It works perfectly fine for me!

 

[acidrain]

Yeah, I don't get the "cheap refractometer" thing. They are simple prism based gadgets that work very well on temperature stable sugary liquids.
Unless your reticle is moving around, or some other means of mechanical failure is happening, you should have a stable reading. It may not be accurate, but it should be stable.
Lot's of refractometers were made with in-accurate scales (i.e. even when calibrated to zero, it is off at upper scale), but that's not what you're describing.
Throw that thing away and get a $29 one.

 

[MeanLowerLow]

During the boil I used to cool samples on a spoon before dripping it on the refractometer. I was getting inconsistent and high readings. Now I understand that you should get hot samples onto the refractometer and close the plate asap before the water vapor escapes. Give the refractometer a couple seconds and it should be an accurate reading. Is this the problem you're having?

My refractometer was $30 with ATC. It works perfectly fine for me!

I've been cooling on a spoon as well, because the hot samples readings seem to raise significantly as they cool. So you're saying get a hot reading and trust it, even though the reading will continue to raise until it has cooled?

 

[GrainToGlass]

I've been cooling on a spoon as well, because the hot samples readings seem to raise significantly as they cool. So you're saying get a hot reading and trust it, even though the reading will continue to raise until it has cooled?

Yes. The couple of drops should cool very quickly once it hits the refractometer even with the top plate immediately closed. The reading will be a bit foggy for a couple of seconds, then clears up and gives me a good, consistent reading. It will raise a couple of points as it's cooling in the refractometer, but not as much as leaving the sample out on a spoon to cool before measuring. Maybe someone can correct me with this method.

I feel this way you get an instant reading of the wort's gravity in the BK at that moment. If you allow the sample time to cool you're allowing the steam (water) to escape, thus the sample appears stronger than what the BK actually is.

 

[McKnuckle]

I understand the science you are promoting there - evaporation leaves the small sample further concentrated, resulting in a falsely high gravity reading - so why not counter it with a larger sample?

I pull a shot glass worth of wort, let it sit for 30 seconds (in which time it cools enough to stop steaming), stir it with the dropper, and pull a few drops from there. Often I'll repeat with the same sample to confirm that the reading is the same. It typically is.

I sometimes use a heavy stainless steel cappuccino cup for this, which acts as a rapid heat sink.

 

[fnbrew]

I just give the kettle a quick stir and grab a couple drops from the spoon straight to the refrac. and read it. If the reading is really off I find it is due to some hop debris in the sample. I trust mine enough that I now brew to a predetermined gravity( flame out is when the refrac. says it is). This may change the end volume a bit but not much. BTW mine was like $60.

 

[eric19312]

Ive got a couple of the $30 refractometers and I use both for each measurement. Normally get same reading and if so I'm satisfied. This wasn't my original plan but thought my first was broken and bought the second, then figured out how to adjust calibration.

I use the shot glass and will put a small piece of plastic wrap on it. I drop the glass into ice bath left over from measuring pH of my mash. But if I don't have the ice batch or the shot glass handy I've go straight from kettle to refractometer without much problem.

I really only use the refractometer right now for pre boil gravity. If my preboil volume and gravity are on target I find I can boil to volume and hit my number within .002 SG every time. If I overcollected from mash (oops) I look at calculated efficiency. If that tracked what I set in the recipe design then again I know I can boil to design volume target and be right on my target OG. Boil harder or longer. If Preboil gravity is low at target preboil volume I have a few options but generally will collect a bit more sweet wort and then boil harder/longer to reach target OG.

I always measure OG and FG using my hydrometer from chilled wort on way to fermentors.

 

[NeoBrew]

I was getting inconsistent readings when I first started using mine. I realized that my cleaning practice was causing the problem. In between samples I spray it with RO water and then dry it off.

What I learned is that it has to be ABSOLUTELY dry. In the beginning I might leave a few streaks of water on the glass. Since the sample is so small, even that little bit of water can easily throw you off a few points.

Since I fixed my practice and make sure to dry it right after a reading and leave it open to dry in between readings. Haven't had that problem since.

 

[JohnnyBrewGood]

Cheap or not, don't drop it.
I did :-(
My reading is now slanted. Can I ever trust it again?

 

[fun4stuff]

Yeah, I don't get the "cheap refractometer" thing. They are simple prism based gadgets that work very well on temperature stable sugary liquids.
Unless your reticle is moving around, or some other means of mechanical failure is happening, you should have a stable reading. It may not be accurate, but it should be stable.
Lot's of refractometers were made with in-accurate scales (i.e. even when calibrated to zero, it is off at upper scale), but that's not what you're describing.
Throw that thing away and get a $29 one.

I love my cheap $20 refractometer. You shouldn't have to pay much more than $30 for one of these- it's not a complicated device.

You don't need to cool it ahead of time. As acid rain says, just take a couple drops from hot wort and place on cool refractometer and close the lid. It will be cooled to room temp in seconds this way. You can also take a very small amount in the dropper and let it sit in that for a mins to partly cool it. No need to cool it a separate cup like you do for hydrometers when you only need a few drops- this is a major advantage to refractometers.

Additionally, if you want an accurate reading it's not good enough to just calibrate with room temp water. You need to determine the wort correction factor that is specific to your refractometer by recording measurements with both your hydrometer and refractometer for several different unfermented samples. Refractometers were originally designed for wine/sugar water, so the scale is not the most accurate for beer wort. Read more about how to do this:

http://www.brewersfriend.com/how-to-determine-your-refractometers-wort-correction-factor/

They recommend 30 samples. But I found after ~10 samples from doing a few multi step starters and a couple brews that my average correction factor was pretty consistent. Now my refractometer matches hydrometer readings. Didn't even use my hydrometer with my last brew.

 

[philipCT]

Okay, so no one out there is using digital refractometers? I've seen some pretty positive reviews of the Milwaukee device.

 

[WI_Wino]

Do you have troubles reading your refractometer, as in the line is blurry?

Or do you get a nice crisp line but the value changes when you do three readings?

If you are getting a crisp reading but the values are different then I'm not sure a digital refractometer will give you more consistent readings.

 

[Homercidal]

When I take readings I pull a few drops into a plastic pipette and submerge the bulb in a glass of 65F water for a minute. Cools it down quick.

I can't see how a refractometer can change it's values like that. It's a prism. No moving parts. Unless, as has been stated, the scale is free and moving around. I don't think that's happening.

 

[kombat]

I only use my refractometer when doing 1 gallon batches (because the volume required for multiple hydrometer readings at that scale becomes non-trivial). For my 5+ gallon batches, I just use my hydrometer.

 

[philipCT]

Do you have troubles reading your refractometer, as in the line is blurry?

Or do you get a nice crisp line but the value changes when you do three readings?

If you are getting a crisp reading but the values are different then I'm not sure a digital refractometer will give you more consistent readings.

I get some of the blurry stuff but mostly I get the well-defined but widely varying readings where the line is pretty crisp.

I've been using this thing for more than a year now and I have had this issue repeatedly. Only after analyzing the readings after the fact did I see the pattern that reflected a recurring inaccuracy.

Shouldn't I expect that a better instrument would give me improved accuracy?

 

[WI_Wino]

If the instrument is at fault, then yes. But as others have pointed out, a refractometer is a very simple instrument. If the issue is in your process a digital hydrometer might not change that.

 

[drgonzo2k2]

Okay, so no one out there is using digital refractometers? I've seen some pretty positive reviews of the Milwaukee device.

Yes, I use the Milwaukee MA-871 digital refractometer, and I like it quite a bit.

Keep in mind though that it's still a refractometer, so everything that has been said here still applies.

You need to take lots of samples (I use the Brewer's Friend spreadsheet someone else mentioned) to figure out your wort correction factor and apply it to your readings every time.

 

[Natdavis777]

I started having issues with mine awhile back. I would calibrate it with distilled water, and verify it with the hydrometer. Then make a wort solution of a known gravity, confirmed with the hydro, but the refractometer was always off. It was always reading low. Since I do 10 gal batches, I just stick with the hydrometer.

 

[PeteNMA]

My refractometer is a $20 cheapy unit from a random Amazon seller, I calibrate it using tap water and the only real issue I have with it is that the line is always a little fuzzy. I either use plastic pasteur pipettes to sample the wort, or just dip the thing into the kettle and sample that way, either seems to work just fine.

Having bought a final gravity hydrometer and dropped the thing after three brews I'm loathe to buy another one, whilst I still have a triple scale one I hate using it, as pulling samples, degassing etc etc is a real pain.

 

[fun4stuff]

I started having issues with mine awhile back. I would calibrate it with distilled water, and verify it with the hydrometer. Then make a wort solution of a known gravity, confirmed with the hydro, but the refractometer was always off. It was always reading low. Since I do 10 gal batches, I just stick with the hydrometer.

That's because you need to calculate the wort correction factor which almost no one realizes they need to do this

 

[philipCT]

If the instrument is at fault, then yes. But as others have pointed out, a refractometer is a very simple instrument. If the issue is in your process a digital hydrometer might not change that.

I hear you. But I believe my process is good. I'm meticulous to the point of obsession. I've described my process in the OP. If you see any flawed or weak points I'm all ears.

 

[grrickar]

Shocking confession - I have a refractometer and a hydrometer, but use neither. I enjoy my beers and enjoy the freedom of not caring the ABV of the final. I follow the same processes to repeat results, and I don't get wrapped up if something is less or more.

When people ask, I guesstimate based on my efficiency. I warn them about the higher ABV beers, especially my friends who typically swill Bud Light and such.

I use the airlock activity to determine when I am ready to bottle, and I use samples to tell me if the beer is overly sweet and something is wrong.

Life is too short to sweat the details such as this in my opinion.

Now if I were competing I may care a bit more, but I brew beers I and my buds enjoy, and I don't worry about the minor details.

 

[fun4stuff]

I hear you. But I believe my process is good. I'm meticulous to the point of obsession. I've described my process in the OP. If you see any flawed or weak points I'm all ears.

Yeah your weak point is you don't know your wort correction factor.

 

[GrainToGlass]

Shocking confession - I have a refractometer and a hydrometer, but use neither. I enjoy my beers and enjoy the freedom of not caring the ABV of the final. I follow the same processes to repeat results, and I don't get wrapped up if something is less or more.

When people ask, I guesstimate based on my efficiency. I warn them about the higher ABV beers, especially my friends who typically swill Bud Light and such.

I use the airlock activity to determine when I am ready to bottle, and I use samples to tell me if the beer is overly sweet and something is wrong.

Life is too short to sweat the details such as this in my opinion.

Now if I were competing I may care a bit more, but I brew beers I and my buds enjoy, and I don't worry about the minor details.

You sir, have mastered the art of RDWHAHB.

 

[drgonzo2k2]

Here's what I would do before investing in another refractometer (although the MA-871 is a bad a$$ piece of kit, so I won't discourage you from buying it)...

- Switch to using your hydrometer as your primary instrument on brew day and your refractometer as your secondary.

- During this time, follow the Brewer's Friend instructions and fill out their spreadsheet completely (30 entries) to determine your wort correction factor. This is really just taking measurements on both instruments and recording them.

- When done, and you know your wort correction factor, try another brew day using your refractometer (with correction factor) as your primary instrument, comparing readings between the two

Hopefully that solves the issue, and if not, then I'd trust that you somehow got a bogus refractometer and can move on to getting a new one. Either way though, since you're using two instruments during all of this, the chance of making another big brew day mistake should be pretty low.

 

[ArcaneXor]

Particulates can skew the reading. Try to minimize picking up grain particles, hop particles, and protein scum.

 

[WI_Wino]

Here's what I would do before investing in another refractometer (although the MA-871 is a bad a$$ piece of kit, so I won't discourage you from buying it)...

- Switch to using your hydrometer as your primary instrument on brew day and your refractometer as your secondary.

- During this time, follow the Brewer's Friend instructions and fill out their spreadsheet completely (30 entries) to determine your wort correction factor. This is really just taking measurements on both instruments and recording them.

- When done, and you know your wort correction factor, try another brew day using your refractometer (with correction factor) as your primary instrument, comparing readings between the two

Hopefully that solves the issue, and if not, then I'd trust that you somehow got a bogus refractometer and can move on to getting a new one. Either way though, since you're using two instruments during all of this, the chance of making another big brew day mistake should be pretty low.

I understand calculating the wort correction factor to get an accurate sg measurement but I don't that think that would affect the repeatability issues the OP is seeing with his refractometer.

The advice on ensuring no particulates are on the refractometer window is good imo.

 

[fun4stuff]

I understand calculating the wort correction factor to get an accurate sg measurement but I don't that think that would affect the repeatability issues the OP is seeing with his refractometer.

The advice on ensuring no particulates are on the refractometer window is good imo.

Particulates can blur the line. Additionally he says he stirs well to minimize stratification. OP states all are off by 0.5-0.7 consistently. That's because he did not us wort correction factor to get true SG. Based on SG, his wort correction factor is most likely 0.95-0.96.

 

[WI_Wino]

Particulates can blur the line. Additionally he says he stirs well to minimize stratification. OP states all are off by 0.5-0.7 consistently. That's because he did not us wort correction factor to get true SG. Based on SG, his wort correction factor is most likely 0.95-0.96.

I see what you are saying. Im going to back track a bit and say figuring out the wort correction factor is a good first step.

 

[Horseshoot]

Maybe I have just been lucky, but when I have measured brix, with my refractometer, it always agrees with what I have seen when measuring specific gravity, with a hydrometer. And when I get a blurry line, I simply adjust the eye piece to my eye, and it sharpens up. Maybe I am missing something?

Mike

 

[fun4stuff]

Maybe I have just been lucky, but when I have measured brix, with my refractometer, it always agrees with what I have seen when measuring specific gravity, with a hydrometer. And when I get a blurry line, I simply adjust the eye piece to my eye, and it sharpens up. Maybe I am missing something?

Mike

You wort correction factor must be 1. Other people have reported having 1 as theirs as well.

https://m.reddit.com/r/Homebrewing/comments/42x7ea/refractometer_users_whats_your_wort_correction/

 

[Yesfan]

I always thought the WCF is nothing more than taking a Brix reading and times it by 4 (Mine doesn't have a SG scale). I do use Brewzor and have entered the Brix amount to double check it and it's usually at most just one point off (ex: 15Brix is 1.059 instead of 1.060). I'm not going to lose sleep over one gravity point.



My refracto has ATC, so I just take a spoon of wort, drizzle it on the refractometer, then take a reading. I don't even use the dropper that came with it. The line is blurry at first, but once it clears up, I then mark what the gravity is (Brix times 4). After each reading, I rinse it with water then dry it. I also make sure it's calibrated before each brew session. I rinse and dry after each reading and not before as I'm afraid any residual rinse water I didn't get dried off will skew the reading.

 

[ittybittykittycommittee]

Mine is terrible. Despite repeatedly calibrating it is always off by at least 0.1 from my hydrometers. It was definitely a waste of money.

 

[philipCT]

Yeah your weak point is you don't know your wort correction factor.

Okay, got it. That is definitely something I've learned from this thread (how could I have not known that before???) so I will bone up on that process and get that taken care of.

Thank you!

 

[Sudz]

I so wanted the refractometer to work. I do have a decent one and it does present a stable display however, repeatability is poor. I simply cannot trust the readings from one brew or sample to another.

It works well with sugar water dilutions but not with wert. Even my lighter brews are questionable. After a considerable effort of trying to find a suitable method of obtaining viable results, I threw in the towel.

Talking with local brew club members, it was common knowledge that these do not provide the level of accuracy required for brewing. Virtually no one used them for brewing however, a number of guys did say they worked reasonably well for making wine.

 

[UndeadFred]

I must be lucky, mine is good enough for government work compared to the hydrometer, and I check it often. It's very nice for taking spot relative measurements. One comment.. you can use RO or even tap water to clean between reading, but use DISTILLED to calibrate it. Try calibrating the unit with distilled and then put a drop of even very low (<10) TDS RO water on it. It'll read 1-2 Brix...

 

[ajdelange]

It works well with sugar water dilutions but not with wert.

Thats because it is designed for use with sucrose - not wort.

Talking with local brew club members, it was common knowledge that these do not provide the level of accuracy required for brewing.

It is well known by some but judging from the number of people who try to use them in brewing I wouldn't say the knowledge is common.

Virtually no one used them for brewing however, a number of guys did say they worked reasonably well for making wine.

That's because must is mostly sucrose and invert sugar which has RI that tracks concentration much better than extract in wort does.

 

[fun4stuff]

I so wanted the refractometer to work. I do have a decent one and it does present a stable display however, repeatability is poor. I simply cannot trust the readings from one brew or sample to another.

It works well with sugar water dilutions but not with wert. Even my lighter brews are questionable. After a considerable effort of trying to find a suitable method of obtaining viable results, I threw in the towel.

Talking with local brew club members, it was common knowledge that these do not provide the level of accuracy required for brewing. Virtually no one used them for brewing however, a number of guys did say they worked reasonably well for making wine.

That's because most people do not know how to use them with beer. You need to figure out the wort correction factor specific to your refractometer.

http://seanterrill.com/2012/01/06/refractometer-calculator/

http://braukaiser.com/blog/blog/2012/03/23/dont-trust-your-refractometer-blindly/

http://www.brewersfriend.com/how-to-determine-your-refractometers-wort-correction-factor/