Just when you think you understand this stilling lark..........

[Phantom]

last weekend, I ran a batch of wash in my SS super reflux.
It was nothing special, just a normal SS triple distilled turbo, so about 14% ABV wash.
I\'d changed the packing in the reflux chamber to copper mesh, and packed it down moderately tightly so it was in line with the top of the cooling collar on the reflux chamber. The mesh would have been about 1 meter or so, if laid out flat.
I fired it up about 1300 and didn\'t switch it off until 2300. It seems that when I have the water supply on full it (the still) will sit at almost exactly at 80 degrees C. There\'s a bit of fluctuation in temp, presumably because of mains pressure variation and it sometimes goes up to 80.3 C, or down to 79.4 C.
That run gave me about 3750mls at 87% ABV (I was periodically measuring and some of the time it was 88% ABV so the 87% is the average).
Yet today, I mixed up all the turbos that I\'d run as \"stripping runs\", let them down to 40% ABV and that went into the still (about 20litres or so). I fired it up at 0900 and switched it off at 1500, getting a total of about 11 litres at 80%. Now yes, I expected it to run a bit faster as there was more alcohol in the charge, but I also thought it would come out a bit higher i.e. at least 88% as that\'s what I got last weekend from a standard turbo wash......
I\'m not displeased, far from it, I\'m just really confused as to why it would only come out at 80% (and yes, it\'s now all been let down to 40% ready for carbon filtration - happy as larry, because it\'ll keep me in drinkies for a week or two :-P ).
As I say, really strange why the 14% wash gave me 88% yet the redistill of the stripped turbo (@40%) has only resulted in 80% spirit......

[Opus 27]

Phantom

I don\'t actually do striping runs I just take my first run cut it back to 40-45% and carbon filter. My last 4 runs have all come out at 92% ABV on a first run using the same still as yourself but I have my column packed with 3 Stainless pan scrubbers. I also drop the power on the element to about 800 watts once up to temperature. Temperature fluctuates between 78 and 80 degrees C. A 16 Litre wash usually runs for about 12 hrs from start up to finsh.
Opus 27

[bluecap]

Hi Phantom this is just a guess but is it possible that the alcohol hydrometer reads all alcohol i.e. the bits we don’t want, taken of at higher temperature but re-distilling you are forcing just the ethanol out by keeping the temperature down and leaving the crap alcohol behind
Just a thought after a few Vodkas… Happy days

[HangOver]

it might depend when you measue % if its straight out of the still it wil read higher as its still, (pun intended) warm

[hoppinmad]

round of applause for that one hangover, and another for making me feel better as im not the only one awake and posting at this time on a sunday morning,
cheers, hoppin

[Phantom]

Nah, HangOvers pun is rubbish..... it comes out at less than 20C so trying to work out why it\'s so erratic at being consistent is really weird.
I don\'t have any way of controlling the temperature. I never did manage to work out how to regulate the voltage/wattage etc (mainly laziness and lack of focus on my part, I don\'t want to have to fanny around, just for \"it\" to work)........

[hoppinmad]

I\'m thinking it probably does work and the missing 8% is left in the boiler with everything else