StillSmart

Thought I\'d open up a \'New topic\' heading.

I made a graphic to explain the proper reading of the scale of a hydrometer like the one I use. Which I found very confusing at first. I thought I was getting readings of 0.890 when, of course, it was 0.989.

Also I have a refractometer, which is very useful, but measures 0-80% w/w.

Anybody know how to make easy conversions to alcohol by VOL without resorting to higher maths!
Ronbo.

The easiest method I use is:
1) pitch in sugar, dissolve. Measure SG.Lets say: 1090 as this is common with 6kg of sugar.
2) Let fermentation finish.
3) Measure SG. Lets say 985.
4) To calculate ABV: (1090-985) / 740

In this case: 105 / 740 = 14,1%
5) distill
6) enjoy

Hi Brewmeister,

The point of the graphic was to show that, on my hydrometer, the figures in grey are not marked, so the readings can be misinterpreted.

When using a pure sugar wash it is hardly worth taking an initial gravity reading, you know what it should always be for 25 Litres total, ie:
4kG 1.061 yielding 9.4%

5kG 1.077 yielding 11.8%

6kG 1.092 yielding 14.1%

7kG 1.107 yielding 16.5%

8kG 1.122 yielding 18.8%
Thats all assuming a perfect ferment. The formula I use is O.G. - F.G. x 129 = %
So in your example that would be 1.090 - 0.985 x 129 = 13.5%
But hey, let\'s not get too anal about the figures, if it tastes good that\'s what counts!

Ronbo.

My request about conversions was specifically; how to convert w/w% to v/v% for different concentrations of Ethanol / Water mixes. For example the beer brewing guys seem to rely on multiplying by 1.25, so that a 3.5% w/w would be 4.4% v/v (ish) But I don\'t think that holds up for higher concentrations, e.g. 60%.

Hence the original question. Yes I have a good alcometer, but it\'s sometimes convenient to measure from just a few drops with the refractometer.

Ronbo.