Refractometer question

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Vongo

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Vote yes or no please.
Has a Refractometer had a positive impact on your brew day and was it worth the investment ?
 

ArcaneXor

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Not really, but mostly because I don't really measure SG any more.
 

Walker

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I love mine. And it's a heck of a lot more durable that a hydrometer. It's not all that expensive either. You can get them for $30.
 

stubbornman

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Love my refractometer. You can make adjustments on the fly and you only need a drop, not a jar full.
 

belmontbrew

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I recently bought one from eBay and brewed my first batch with it. It is awesome! I never had much luck using hydrometers so I just stopped checking SG. The refractometer showed me how poor my mash efficiency was, and I was able to correct that batch. I also used it in conjunction with open fermentation (no bubbles) to see how things were going and pick a time to dry-hop. It is so simple to use and was $30 with shipping.
 

BeerNut24

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Are there different types of refractometers? I have one I use for saltwater aquariums. Would this work for Beer / wine also?
 

ayoungrad

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I just bought one but haven't recieved it yet. Looking forward.

As far as saltwater refractometers. In looking around the net, some refractometers seem geared toward sugar and others salt but I'm not sure that will make a difference...
 

ayoungrad

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Just did a google search. At least some people had no luck with a saltwater refractometer. You could try and compare results from it to a hydrometer but it sounds like it is a no-go.
 
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Vongo

Vongo

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Home brewers are the best ... Thanks for the feedback! I am really interested in post boil gravity reading with out using so much wort and no need for temp correction.
Thing that stinks is I must buy yet another tool for my home-brew interest :0). You all got my back if I need documentation for my wife, right ?
Cheers!
 

beercheer4me

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They make them with S.G. And brix scaled side by side,, I like mine, just drops, not the waste, like they say, makes checking on the fly petty handy
 

o4_srt

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The only reason a saltwater refractometers might not work with beer is that saltwater is usually between 1.020 and 1.030. Most beers og is obviously many points above this, so the scale of the saltwater refractometer might be too low.
 

OldManHouston

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Bought mine off ebay for around $30. I love the ease of being able to check my pre-boil gravity as well as checking at various points during the process to see how close to my target I am. After a few brew sessions with it, I now feel like I can adjust my wort at different points in the process to ensure the end product I'm getting is what I was planning for.
 

stevedasleeve

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Nope. I find mine to be slightly superfluous. I use it as a matter of course - and note if anything is wildly off, though it never is these days - but frankly a few points here and there just don't seem to make a difference at all and my calculations are always pretty much on. I am more interested in FG and for that I use a hydrometer since I have found my refractometer inaccurate for finished beer. Also I prefer to have enough to taste before I keg the beer. YMMV but I'd just as soon spend money on more hops if I had it to do over.
 

ayoungrad

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Yup, this one does but costs a little more.
That's the one I ordered. The only conversion I'll have to do is the one accounting for alcohol content on my FG - and I'm sure I can shove that into my brewing spreadsheet pretty easily.
 
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Vongo

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I thought they were no good for final gravity ?
 

ayoungrad

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It's my understanding that you can use a conversion to determine the effect of alcohol content on the SG. They have conversion charts all over the net including on the link above to AHS. Not sure how accurate it is bc I haven't looked into it yet but my guess is that its pretty accurate. After all, ABV is really just a function of OG and FG so with 2 SG values you have a really accurate measure of the amount of alcohol and water in the beer.
 

Whut

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I don't have the one I linked - I just had seen it before on the AHS site. Mine just shows Brix and then I use the spreadsheet MoreBeer provides to do the calculations.
 

rico567

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I use my refractometer exclusively now, except for the eventual FG reading, which I still take with my hydrometer. Makes brewday easier, was less than $30 on eBay. I don't understand the fascination with the ones that do SG.......guess I'm not all that precision-minded, I just multiply the Brix reading X 4.....
 

Golddiggie

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Used the one Bobby_M sells on Thursday's brew evening... It has both Brix and SG scales on it, so you don't need to do any math to get your pre-boil gravity, or OG numbers. I'll probably write down the Brix numbers for the OG, so that I can enter it into the tools later. I think it sucks that the tools don't give you the option of using either Brix or SG readings. IMO, they should.
 

ayoungrad

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Did your refractometer come with equations for correcting the refractometer FG to account for EtOH? I'm trying to set-up my brewing spreadsheets to incorporate the refractometer I ordered. I looked briefly on the net and most of the equations I find include either a temperature correction which I don't need (it has ATC) or are only relevant to Brix - is this what you were referring to Golddiggie?

Anyone find an accurate equation for a refractometer using SG and ATC?
 

williamnave

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IMHO - refractometers are fantastic for brewday, but absolutely useless once yeast is in the equation.

I've tested those calculators against what a hydrometer reads, and they are not at all accurate.

I love my refrac. and it is very helpful on brew day. Be sure you get one with Auto temp control. For final gravity, I bought a narrow-range (.95 - 1.020) hydrometer at my LHBS for 20 bucks. So refrac. on brew day, ultra accurate hydrometer for FG.
 

ayoungrad

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IMHO - refractometers are fantastic for brewday, but absolutely useless once yeast is in the equation.

I've tested those calculators against what a hydrometer reads, and they are not at all accurate.

I love my refrac. and it is very helpful on brew day. Be sure you get one with Auto temp control. For final gravity, I bought a narrow-range (.95 - 1.020) hydrometer at my LHBS for 20 bucks. So refrac. on brew day, ultra accurate hydrometer for FG.
I'm planning on using both at first. How far off was the refractometer? Inherently it seems that the correction would be accurate. Which correction did you use?
 

HairyDogBrewing

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I use mine to measure each running of the batch sparge.
So I'll have some data when I decide to do some partigyle batches.
Then I get a reading for boil gravity, if it's lower than expected I can add extract.
These are all hot wort and I don't have to wait 10-15 min for a hydrometer sample to cool to room temperature.
Just put an eyedropperful on a tablespoon for a few seconds, then draw a few drops for the refractometer.

For OG and FG I take both hydro and refract readings.
Again, for the sake of data acquisition.
You need to determine your brewhouse correction factor (about 1.04).

During fermentation I sterilize an eyedropper or pipette and I can get an idea of how fermentation is going without wasting a glassful of beer.
I use the refractometer tool in BeerSmith to convert Brix to SG for fermenting wort.

Also, the refract tool will estimate the OG and alcohol content of a finished beer, if you want to clone a commercial product.

A refractometer is hours of fun and has a great MSF (mad science factor).
I wouldn't give mine up, but I can't say that it has directly improved my beer.
 

ayoungrad

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What is the basis of a brewhouse correction factor?

For my hydrometers (I have one high grav and one more accurate low grav) I use temperature correction and calibration correction only.
 

br1dge

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I love my refractometer. As everyone else has said it cuts down on the waste and lets me take more measurements very quickly. Its nice to have a hydrometer around every once in a while but I would definitely recommend using a refractometer if you dont currently.
 

BeerIsDelicious

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I have an app in review by apple at the moment called RefracTool, that will do the work of the spreadsheets linked to in this thread -- check for it in a week or so. I originally made it just for myself, but it's helped me greatly so I decided to spruce it up a bit and release it to the masses.
 

HairyDogBrewing

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What is the basis of a brewhouse correction factor?
One Brix is 4 gravity points - for sucrose.
The refractometer is off a little bit for wort, so there is a small correction factor.
So if you take OG with both hydro and refract you'll see what correction is needed and put that number in BeerSmith's refractometer tool.

I think Yooper helped to develop this, so maybe she can explain it better than I can.
 

williamnave

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I'm planning on using both at first. How far off was the refractometer? Inherently it seems that the correction would be accurate. Which correction did you use?
5-10 points. My experience was a little limited, but I was steered towards my current methodology by very experienced brewers whose opinion I value.

I found that I could take readings up to a point with a refractometer, and then they would spike when alcohol content got too high.

i.e. OG 1.065

2 days later 1.052

4 days later 1.038

6 days later 1.024

8 days later 1.041

Now, unless there's some serious funny business going on, sugar didn't immaculately conceive itself in my fermenter. I experienced this across quite a few brews, each time taking brix readings, plugging them into BeerSmith, and getting SG out. As I came to understand it, when the alcy content reaches a certain point, the refractometer gets a little unpredictable. Even the most perfect model designed by a MIT hit squad wouldn't be as reliable as floating a hydrometer in it. I now leave my beers in primary for a month or more, and take a FG reading prior to kegging just to make sure all went well.
:fro:
 

jkarp

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I'm planning on using both at first. How far off was the refractometer? Inherently it seems that the correction would be accurate. Which correction did you use?
Doesn't matter. Refractometers measure brix - a measure of the sugar content of an aqueous solution. After yeast convert the sugars to alcohols, which have entirely different refractive properties, brix refractometers are as effective at determining gravity as sundials. Yes, people have tried to formulate "corrections" for alcohol. Yes, they all suck as anyone who's done side-by-side tests know. Still, refractometers are great for pre-fermentation measurements.
 

a10t2

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A couple things:

The refractometers that have SG scales (at least all the ones I'm aware of) aren't correct. The manufacturer(s?) used the "multiply by four" rule instead of actually putting in a conversion.

They're calibrated for sucrose solutions, but wort is primarily maltose. Typically you convert by dividing by 1.04 - so a reading of 20°Bx means the SG is actually about 19.2°Bx (1.079).

After fermentation starts, the alcohol in solution will result in an artificially high SG reading. You can try to compensate using an empirical correlation. There are two that I know of: one is included in ProMash, BeerSmith, the MoreBeer spreadsheet, etc. I recently developed the other. Everyone I know of who's tried both has found the standard correlation to be less accurate.

http://seanterrill.com/2011/04/07/refractometer-fg-results/
 

Octavius

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... I recently developed the other...
Many thanks for posting - it looks interesting reading. Can you tell me where the magic number 1.04 originally came from? Or provide a web link, wherein :) I may educate myself.

Cheers!
 
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