Did I get the wrong one?

Desert_Sky · Jun 22, 2006

Well Ive been wanting to get a refractometer for a while now. I won a Salinity Refractometer this morning off Ebay. Pretty decent price too $21.00

Is there much of a diference between a sugar refractometer and a salinity? Both will measure the specific gravity of liquids correct? Does anyone know what the diference is?

I guess If I got the wrong one I'll jsut put it back up on ebay.

heres a link of the same one on a diferent auction

http://cgi.ebay.com/NEW-Heavy-Duty-...0QQihZ018QQcategoryZ20755QQrdZ1QQcmdZViewItem

homebrewer_99 · Jun 22, 2006

(I'm at work and can't check the eBay site)

Is that a brand name? If not, does the "Salin"ity portion identify salt and not sugar?

Desert_Sky · Jun 22, 2006

Heres what the site glass display looks like. I can deal with the salinity % on the right hand side. Im only worried that the gravity reading will be correct. A gravity reading is a gravity reading I thought.

Glibbidy · Jun 22, 2006

Um, it says specifically that the RHSN series of portable refractometers is designed to measure the salinity of sea water and saline solutions of similar concentration.
I'm no chemist here, but if I had to hazard a guess, the unit you got is designed for salt as opposed to sugar content. It is likely they are not designed with measuring the specific gravity of beer in mind. Then again, I'm no rocket scientist either, and I may be totally out of line with my guess.

hijacked from the internet:
SNIP>
It must be remembered that refractometers measure the refraction of light relative to some standard and some substance. For instance a refractometer calibrated to measure the salinity of water can be used to measure a sugar solution, but such a measurement is not accurate for sugar. Likewise, using a refractometer meant for fruit juices is not truely accurate for wort and beer. It is accurate "enough" for wort, since wort is largely simple sugars and their refractive behavior is close to that or sucrose. However, without some "interpretation" it is not accurate for finished beer due to the alcohol content.
SNIP>

Desert_Sky · Jun 22, 2006

great....

Well I guess I could always break out the old hydrometer, take a reading, then compare it to what the refractometer says. If its off or won't take a reading, well back on ebay it goes. I should be able to get my money back at least. Damn, and I was all happy I got a good deal.

Thanks

Spyk'd · Jun 22, 2006

I'm no rocket scientists either, but I'd venture a guess that sugar are salt might be pretty close when it come to concentration disolved in water. Perhaps some research is order...

Desert_Sky · Jun 22, 2006

Yea who knows, it may work. Or even if I can figure out how to compensate for the changes, I could still use it.

Beer Snob · Jun 22, 2006

You know I cant find a refererance to one of these things outside of the wine books I have.... Chimone man, are these supposed to be easier then a hydrometer or soemthing?

MrSaLTy · Jun 22, 2006

A refractometer measures the brix or sugar level from just one drop of wort. Yes it is easier to use then a hydrometer. Brix can easily be converted to specific gravity and you don't have to cool the wort to get an accurate reading. The only downside is they are around 60 bux and you can only measure unfermented wort. You may be able to measure fermented wort with a realy complicated formula but I'm not sure.

BrewStef · Jun 22, 2006

I believe Beersmith can convert FG refractometer readings as part of their "refractometer toolkit".

Download the demo at:
http://www.beersmith.com/index.htm

Brewiz · Jun 22, 2006

I have one that I have borowed from a friend of mine and I will definitely be buying one when he wants his back. They are an awesome tool when sparging, it makes it so easy to check your runnings and your OG before fermentation.

Here is the one you want: http://cgi.ebay.com/NEW-0-32-ATC-Br...ryZ31483QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Desert_Sky · Jun 22, 2006

Beer Snob said:
Chimone man, are these supposed to be easier then a hydrometer or soemthing?

Yea apparently you put one drop of wort on the lens, yea you heard right....ONE DROP!! Then theres a calibrated prism or something the refracts light and tells you the specific gravity of your wort.

Not that I use my hydrometer at all anymore, but I think I might be able to sacrifice one drop to take a measurement reading now.

And Brewiz, where were you this morning bud? heh, just kiddin, I totally screwed the pooch on this one. I saw refractometer for 20 bucks and clicked the bid button.

Does anyone have a marine aquarium they want a refractometer for?

Beer Snob · Jun 22, 2006

Sounds cool. I've read these for wine many times. Although I dont recall it being used for making the wine, but more for growing grapes. I've never done it, but it apparently tells you when the best time is to pick the grapes.

Beer Snob · Jun 22, 2006

Brewiz said:
I have one that I have borowed from a friend of mine and I will definitely be buying one when he wants his back. They are an awesome tool when sparging, it makes it so easy to check your runnings and your OG before fermentation.

Here is the one you want: http://cgi.ebay.com/NEW-0-32-ATC-Brix-Refractometer-Wine-Beer-CNC-Fruit_W0QQitemZ7631177833QQihZ017QQcategoryZ31483QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Hey this one has a potential alcohol scale....

http://cgi.ebay.com/NEW-Alcohol-Brix-Refractometer-4-Wine-Beer-Mead-Port_W0QQitemZ7609756492QQcategoryZ11876QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

johnoswald · Jun 23, 2006

Chimone said:
Heres what the site glass display looks like. I can deal with the salinity % on the right hand side. Im only worried that the gravity reading will be correct. A gravity reading is a gravity reading I thought.

I think you have bought a paper weight. Neither scale is specific gravity.
If I remember my chemistry classes, the scale on the right is not % but %o - which is parts per thousand and calibrated for salinity only. The scale on the right is relative refraction (vs. water) with both samples measured at 20°C.
Please correct me if I am wrong, but there should be a conversion scale for the relative refraction to % sugar (Brix scale)

Desert_Sky · Jun 23, 2006

johnoswald said:
C.
Please correct me if I am wrong, but there should be a conversion scale for the relative refraction to % sugar (Brix scale)

you wouldn't happen to know what that is do you?

Beer Snob · Jun 23, 2006

You know I have absolutly no idea what I'm looking for... but hey... what about these...

http://www.coleparmer.com/techinfo/...htm&Title=Brix+Scale+(sucrose)&referred_id=93

Another site at the same web site that looks good.
http://www.coleparmer.com/techinfo/techinfo.asp?htmlfile=Refractometers.htm

This place sells all those kinds of things and might know how to convert the saline scale to brix...
http://www.nationalmicroscope.com/index.html

What if there are no tables to convert saline to brix.... what if you did this... take a wort sample of a given measurement and load it up. Take the measurement and record where it is on the scale you have. Should be pretty simple to dillute the same sample and take a few readings. Take a few readings.... a few on both sides of the scale... a few in the middle... then you just have to connect the dots using a curve. I would guess you would need a curve for this and it would not be a direct one to one relationship.... man is this stretching the memory of organic chem or what.....

This sounds like a pain, but you would only need to do it once and you have a meter for a lot less then the one in the right scale.....

david_42 · Jun 23, 2006

Since refractometers are actually measuring the index of refraction of a solution, not the actual gravity, conversion tables don't exist. I would make up a solution from table sugar (since it's clear) and calibrate the scale. Four oz. in a pint of water should give you 1.092 (46 points per pound per gallon). Take a cup of that and a cup of water for 1.046. A cup of solution B and a cup of water 1.023. One more time for 1.011, which is a good place to stop for sparging.

You should get a linear relationship. If 1.092 = 100 (whatever that scale is on the right) 25 would be 1.023.

johnoswald · Jul 3, 2006

Sorry I didn't see this coming and look back here before I went away for a week!
Go to http://www.ams.usda.gov/FV/ppbweb/PPBfilecodes/135a3.pdf. Therein lies a comparison if a hydrometer and refractometer AND on pages 18-24 the conversion scale from refractive index at 20°C to degrees Brix and specific gravity (density) degrees Baume.
Next go to http://www.reefkeeping.com/issues/2004-06/rhf/index.php and there is a conversion table for saline solutions from specific gravity to refractive index.
then use Excel (or the equivalent spreadsheet program) and cut and paste these two tables together so you end up with a conversion from specific gravity (salinity - which you read off your refractometer) to specific gravity (sugar - your wort and sparging run offs).
So to recap....
1) Your refractometer will measure the refractive index of your wort but the scale reports it as specific gravity of a saline solution. 2) The aquarium table converts the saline specific gravity back to refractive index. 3) And the USDA table converts the refractive index into the corresponding sugar specific gravity or °Brix.

So Chimone, I it's not a paper weight but actually a deal!
So instead of making up all those standard solution - make another batch of beer!

Desert_Sky · Jul 3, 2006

johnoswald said:
Sorry I didn't see this coming and look back here before I went away for a week!
Go to http://www.ams.usda.gov/FV/ppbweb/PPBfilecodes/135a3.pdf. Therein lies a comparison if a hydrometer and refractometer AND on pages 18-24 the conversion scale from refractive index at 20°C to degrees Brix and specific gravity (density) degrees Baume.
Next go to http://www.reefkeeping.com/issues/2004-06/rhf/index.php and there is a conversion table for saline solutions from specific gravity to refractive index.
then use Excel (or the equivalent spreadsheet program) and cut and paste these two tables together so you end up with a conversion from specific gravity (salinity - which you read off your refractometer) to specific gravity (sugar - your wort and sparging run offs).
So to recap....
1) Your refractometer will measure the refractive index of your wort but the scale reports it as specific gravity of a saline solution. 2) The aquarium table converts the saline specific gravity back to refractive index. 3) And the USDA table converts the refractive index into the corresponding sugar specific gravity or °Brix.

So Chimone, I it's not a paper weight but actually a deal!
So instead of making up all those standard solution - make another batch of beer!

I really do appreciate all of that info, but im going to need to go open a beer before I get on all those conversions!!! Thanks again bro, I'll get it figured out soon.

Paco · Jan 17, 2009

Then maybe someone can help me with this issue.

Thanks in advance for any help.

Did I get the wrong one?

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