Yes, see the valley vintner. He has a downloaded able spreadsheet for this

Hi Phil,

To my understanding, after fermentation has begun, you cannot really get an accurate reading on the refractometer and that the hydrometer is much more accurate.  It has something to do with the actual fermentation process.

That's what I was told, so I use the refractometer up until crush, then I switch over.  Always possible that what I've been told is wrong, but just passing along what I've heard.

Kathy

7 hours ago, kakeeler said:

Hi Phil,

To my understanding, after fermentation has begun, you cannot really get an accurate reading on the refractometer and that the hydrometer is much more accurate.  It has something to do with the actual fermentation process.

That's what I was told, so I use the refractometer up until crush, then I switch over.  Always possible that what I've been told is wrong, but just passing along what I've heard.

Kathy

You need the pre-ferment refractometer readings.  Then, you can use some estimations/calculations down to the end.  Not as accurate as a hydrometer, IMO but many people use it.

It is not as accurate as hydrometry as mentioned above....but "good enough" to follow the progress of a fermentation.

I have prepared a document describing the process and procedure:

See http://www.moundtop.com/fermentation/RBRIX-ATC-Fermentation-Tables.pdf

The refractometer approach's biggest problem is that it cannot be used to reliably to indicate dryness (end of fermentation).  However, even a hydrometer comes up short here.  As an amateur winemaker I rely upon Clinitest tablets to estimate the residual sugar level indicative of dryness.  As always, there are many ways to skin this cat.

The main advantage to using the refractometer and the tables are to tell when you need to add your Fermaid. If you have a lot of fermenters going then the refractometer would be a lot quicker.

On 6/11/2019 at 3:55 PM, moundtop said:

It is not as accurate as hydrometry as mentioned above....but "good enough" to follow the progress of a fermentation.

I have prepared a document describing the process and procedure:

See http://www.moundtop.com/fermentation/RBRIX-ATC-Fermentation-Tables.pdf

The refractometer approach's biggest problem is that it cannot be used to reliably to indicate dryness (end of fermentation).  However, even a hydrometer comes up short here.  As an amateur winemaker I rely upon Clinitest tablets to estimate the residual sugar level indicative of dryness.  As always, there are many ways to skin this cat.

 

Where can you find clinitest?  I thought Bayer quit making them again

Alas, Bayer Clinitest is no longer available.  I purchased a stash of 200 tablets a few years ago that I continue to rely upon (On occasion, they show up on eBay at a premium price).  As far as I know, an alternative for home winemakers is the Accuvin Residual Sugar Test....but I have no experience with that product.  I would be interested in hearing about other alternatives that don't require a spectrophotometer or reagents with very limited shelf life.

7 hours ago, moundtop said:

Alas, Bayer Clinitest is no longer available.  

Mine finally gave up the ghost.  A company makes them now, sold under AimTab Reducing Substance Tablets.  Of course they cost 2 to 4 times what i could get 100 Clinitest for but the reality is i rarely got through a whole bottle before they went bad so it is what it is.  Maybe they are doing me a favor selling only 36 tab bottles.  I think they do foil packs too.

On 6/11/2019 at 5:18 PM, gwbod said:

The main advantage to using the refractometer and the tables are to tell when you need to add your Fermaid. If you have a lot of fermenters going then the refractometer would be a lot quicker.

But aren't you supposed to add the Fermaid at a 1/3 brix drop?  You shouldn't even need a chart for that.  

For the end of fermentation, we use a specific hydrometer (https://morewinemaking.com/products/hydrometer-brix-5.html), so that it's as precise as we're going to get it.  We always have some oddity with non-fermentable sugars, which are probably just part of growing grapes here, but the more precise hydrometer helps.