Refractometer

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Try this web page, the calculator layout may work for you better:

http://brew.stderr.net/refractometer.html

At the top enter 140 in the gravity and when you tab or click out of the box it will tell you your Brix should be reading close to 32.2 on your refractometer at a temperature of 20 degrees C.

Now this is the only time where Measured Gravity and Brix will agree with each other on a simple straight conversion.

From now on as more alcohol from fermentation enters your liquid it will bend more and more the light the refractometer measures to get its reading. At the beginning with a little bit of alcohol Brix and Gravity are close to each other in value when doing a simple conversion between the two. At the end of fermentation with a lot more alcohol the difference is bigger between the two values.

So we use a second calculator that takes care of the skew. Critical is the original gravity or original brix reading to get original gravity because the calculator needs to know how far down from the value we are currently to determine how much skew needs to be applied to make the end answer accurate.

So on that page down below put in 140 in the Starting Gravity area and as you monitor a ferment with refractometer to not waste your mead on constant hydrometer sampling you put your current Brix reading in. You read 20.6.

Put 20.6 into Brix

As soon as you tab or click out of the box it should tell you that your gravity reading should be close to 1.051 and that the estimated alcohol percentage is 11.9% alcohol in solution.

Volumetic dilution is easy as well if you can't get that last 2% by alcohol conversion you can reduce the gravity in solution with water dilution which is fine as long as it's not a large amount because it will dilute everything across the board: Alcohol, residual sugar, aroma, flavour. Small amounts are unnoticeable and large amounts are noticeable.

If you have exactly 25 liters of 1.050 liquid then water which is 1.000 gravity liquid will be added. If you add 1 litre of water you have 26 liters in the end of total liquid.

So Liquid litres multiplied by Liquid gravity
add to this Water litres multiplied by Water gravity
then divide by the final Combined litres amount.

That's your new gravity amount.

Keep playing with litres of water to dial in a gravity you want to achieve.

You are looking for about 18.5 or so Brix reading in an optimum perfect world with your yeast you used. Or a gravity around 1.036 to 1.038 or so. See if you can find out how much water dilutes to a gravity of 1.040, 1.048 and 1.036 as an excercise. As a further excercise you can find out say with 100mL sample size. Then, as a final excercise you can pull off samples and dilute to each gravity level and taste tem and see if you can tell any difference between both them and the undiluted original liquid.


Cheers,
Brewer Pete
 
Thanks a lot Pete. I was putting in 1140 or 1.140 instead of 140 which was where I was screwing up. It makes more sense now and matches the hydrometer reading which hasn't moved much since the last week.

Cheers,


Moovet
 
Only if you want to raise salt water fish. You need a refractometer that has been made to measure sucrose.

Cheers,
Brewer Pete
 
I came across a Refractometer with 0-40% Brix AND 0-25% Alc on Ebay. Refrac Brix & Alc on Ebay
Looks to be the goods and cheap. On the adage of you get what you pay for: do you think it would be a useful device or potentially cheap and nasty?
What are your thoughts?
 
I got mine off ebay and it was worked well, only wish I had bought the 0-18 Brix as it would make it easy to read accurately (upto 1.070 starting gravity). The 0-40 scale tends to be hard to read a difference between 1.040 and say 1.041 type readings. And given I rarely brew starting gravities above 1.060, the 0-18 Brix would have been a better choice.

Something to think about.
 
I got mine off ebay and it was worked well, only wish I had bought the 0-18 Brix as it would make it easy to read accurately (upto 1.070 starting gravity). The 0-40 scale tends to be hard to read a difference between 1.040 and say 1.041 type readings. And given I rarely brew starting gravities above 1.060, the 0-18 Brix would have been a better choice.

Something to think about.


Thanks John, just the sort of practical advice I was seeking. :) . Seems like you can get them in any manner of ranges and variables...
 
I got mine off ebay and it was worked well, only wish I had bought the 0-18 Brix as it would make it easy to read accurately (upto 1.070 starting gravity). The 0-40 scale tends to be hard to read a difference between 1.040 and say 1.041 type readings. And given I rarely brew starting gravities above 1.060, the 0-18 Brix would have been a better choice.

Something to think about.

Just got myself an 18 Brix one, likewise have not brewed anything above 1.060 OG. Have not used it yet but brew day today.
 
Just got myself an 18 Brix one, likewise have not brewed anything above 1.060 OG. Have not used it yet but brew day today.

Be interested in hearing feedback. I could be tempted to buy another one and keep the first one for testing my grapes.
 
Since I like to do a yearly batch of russian imperial, I grabbed the 64 brix model that also has the SG scale.

Havent used mine yet, but the time to brew is coming very soon
 
How did I brew prior without one!!

First (well second if you count the comp thread) real post since I went o/s and I just had to give it a mention. I finally bought myself a refractometer (as well as a bunch of other stuff) and must say it is soooo much easier and quicker than the 'ol hydrometer.

Also hit every mark I had to on my first brew day in almost 9 months....

I bought the one from Ross with both Brix and SG, just makes it easier I guess. :)
I should have got one so much sooner.
 
How did I brew prior without one!!

First (well second if you count the comp thread) real post since I went o/s and I just had to give it a mention. I finally bought myself a refractometer (as well as a bunch of other stuff) and must say it is soooo much easier and quicker than the 'ol hydrometer.

Also hit every mark I had to on my first brew day in almost 9 months....

I bought the one from Ross with both Brix and SG, just makes it easier I guess. :)
I should have got one so much sooner.

I got one off Ebay with the Brix and SG but how do you read the damn things. Mine just gives me blue slowly fading to white but it is impossible to pick any particular line like they show in the instructions. I took a guess at 1025 but my hydrometer gives me 1016. Am I doing something wrong?
 
I got one off Ebay with the Brix and SG but how do you read the damn things. Mine just gives me blue slowly fading to white but it is impossible to pick any particular line like they show in the instructions. I took a guess at 1025 but my hydrometer gives me 1016. Am I doing something wrong?
You should be able to focus it by turning the front section (eyepiece).
 
I got one off Ebay with the Brix and SG but how do you read the damn things. Mine just gives me blue slowly fading to white but it is impossible to pick any particular line like they show in the instructions. I took a guess at 1025 but my hydrometer gives me 1016. Am I doing something wrong?


The exact same problems identified on the first page of this post. Make sure the covers fully closed.
 
Bought mine and used it on my last two batches, great tool, wish I had bought it years ago. I make sure its zeroed before each reading and have tested it against my hydrometer each time, no discernable difference between the hydrometer and the refractometer.
 
just to bring this back to the surface, i've noticed in beersmith 2.0 there is a section for the refractometer. I was originally put off with the complexities of FG readings but it seems that beersmith 2.0 will do the conversion from brix to sg in the presence of EtOH.

Has anyone tested this to see if its accurate?

JT
 
just to bring this back to the surface, i've noticed in beersmith 2.0 there is a section for the refractometer. I was originally put off with the complexities of FG readings but it seems that beersmith 2.0 will do the conversion from brix to sg in the presence of EtOH.

Has anyone tested this to see if its accurate?

JT
BeerSmith has always had such a function, its not new with the new version, so one would presume its accurate. :)
 
Just got my first Refractometer :kooi:

I noticed on THIS website it states;

"When looking through the monocular, be sure you are using natural light to view the readings; you should not read a refractometer in the prescence of fluorescent light."

Does this really matter?

I'd like to use it after dark if possible and my shed lights are fluerescent.
 

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