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all hail mighty distillers with vasts amount of knowledge on the subject that i don't possess. Please help me through this one...

Question 1 (primary)
How do i calculate the alcohol content of the emerging distillate from my still to make the cuts at the right times?

I have a proof hydrometer, but it takes a large enough sample to float it that i don't feel like i'm being very accurate. I like the idea of being able to measure a few drops with a refractometer.

I have a refractometer that measures Brix - but for every measurement of ABV you need an OG and TG. Is my OG the one for my mash before i began fermenting? Is it the SG of the low wines before i distill them? I can't make sense of it. Apparently there are such things as alcohol refractometers that i'd be happy to pick up, but they only measure 0-20% ABV.

Question 2 (less important)
i've tried using digital thermometers with probes to measure the temp of my stillhead, but they don't seem to be accurate or consistent, or match up with the exact temps i'm expecting. Am I wasting my time? Should i just buy a regular lab thermometer and watch it closely? I like the alarm feature on the digital ones.


Thank you so much in advance - i'm sure i'm missing something quite obvious, but can't seem to figure it out.
Cheers!

Your cuts should be decided by taste, not ABV. If you want to monitor ABV while your still is running, a parrots beak and alcometer will do the job.

you might want to have a glance through this if you're battling a bit with cuts. http://homedistiller.org/forum/viewtopi ... 15&t=11640

Cuts are hard to get right at first, but you'll find yourself getting better and better at picking the tastes the more you do it.

What I do is use a small 0.1g accurate scale and a 20ml syringe. I zero the scale with the syringe on it, decant a small sample in a jar, pull a syringe full and remove air bubbles, then weigh the sample and divide by the volume to determine specific gravity. I used excel to plot the sp. gr. of differnent mixtures of ethanol and water and obtained the equation of the line and backed it out to the following formula. I've checked with water and denatured alcohol and it seems to be relatively accurate but not quite as easy or cool looking as a parrot and alcoholmeter.

(SG - 1)/-0.211 = % ethanol

SG and OG are the same thing. This is the reading of potential alcohol you get when you start your ferment. Subtract that from the reading you get when it's finished fermenting to get your actual %abv of the mash before it goes in the still. You use a beer and wine hydrometer to do that. After a run through the still you need a different hydrometer, a proof hydrometer, which is calibrated for higher %abv. They only cost a few bucks and are a must have.

Don't try to use the %abv to make cuts. there are some good stickies in the novice section that explain cuts very well. The best way is to do it by taste and smell. Read the stickies to figure out just how to do this. It's something that will take some practice so be patient.

besides the link kiwi posted the first post in the "distilling advice" sticky is full of good info.

An alcometer will probably the cheapest thing you will buy for this hobby. Its a must have item.

olddog wrote:An alcometer will probably the cheapest thing you will buy for this hobby. Its a must have item.

Buy two while you are about it, you are sure to break one!

Build a parrots beak. If done correctly, you can get as small as a 75ml sample to float it. A refractometer meant for brix isn't going to tell you a thing.