copper pot still clean up

Simple pot still distillation and construction with or without a thumper.

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stillvodka
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copper pot still clean up

Post by stillvodka »

Hello All,

I have finally finished my Pot Still build, after something like 2-3 months , the head is all copper with lots of Soldering fabrication done to it, looks like a copper pot scottish whisky still , Because of all the soldering and grinding/cutting I have done it has got very mucky inside, my other stills I v'e had were always straight pipe or stainless ''easy clean', this one has more shapes to it, I need to give it a real good flush out, What is the best methods for a good clean with this style of pot still, I have read on here people fire their still up and running Lemon and vinegar, what sort of quantity or mix ratio recon best ?

Thanks
Hawke
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Re: copper pot still clean up

Post by Hawke »

I used a litre of Realemon and 1/4 cup non-iodized salt in about 3 gallons of hot tap water to soak mine. Plug one end and fill it up. It will clean up the bare copper in just a few minutes. If you have a carboy brush, you could put a bend in it to scrub the contours. Rinse it well or it will turn green.

Once you soak it, run a 1L per gallon vinegar wash through the still. (If you have an electric, you need enough to keep the element covered. If you are using gas, just a gallon or two.) Check all joints for vapor leaks during this run.

Next, use some cheap wine or a quick sugar wash for the first alcohol run. This should clean out any flux not removed in the first two goes. Don't drink any of this first run stuff. Dump it, or use it again for further cleaning or practice.
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stillvodka
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Re: copper pot still clean up

Post by stillvodka »

Thanks for the advice Hawke, it's most appreciated,
Usge
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Re: copper pot still clean up

Post by Usge »

Lemon/salt will absolutely strip copper down nekid. I've heard of using it on the "outside" but ain't never heard of using it on the inside. Other than that, I'm sure it works! (ie..down to the shiny copper metal). Dunder, and others, have said just use hot-slops from a stripping run to soak it. I know that sure enough makes the bottom of my pot clean after a stripping run.

Using vinegar and or vinegar/water soak was also something recommended, and something Iv'e used. But a friend of mine who's a plumber, and whos also familiar with distilling, suggested that the copper could absorb the vinegar and it could eventually ruin your still (ie., could give off-tastes). He also said lemon salt used all the time would just eat your still away to nothing. Since then, I've used only water to flush out my still and I can definetly tell my still heads need some cleaning.

Seems to me, it makes sense that if copper is absorbing some of the bad stuff that over time it would start imparting off-tastes to your distillate. And it makes sense that something that strips it down to bare copper would be the surest way to do that. I just recall from somewhere, can't remember where, being specifically warned "against" using lemon/salt on the inside. And my plumber/distiller friend has said vinegar would permeate the copper and ruin it (for flavor/taste). I guess that leaves the tried and true "hot slops" method.


Just wondering outloud if anybody who's used any of these various methods of cleaning has noticed any off-tastes or other issues develop over time?
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Re: copper pot still clean up

Post by Hawke »

Usge,
The lemon/salt is only for initial cleaning. It will get rid of all the oxidation caused by the torch.
The vinegar is another acidic solution that will break down most of the flux.
Once you run the first etoh through, it should strip any flavor out and start adding the patina to the insides.
I never do more than hot water rinses between runs.
It is the very things that we think we know, that keep us from learning what we should know.
Valved Reflux, 3"x54" Bok 'mini', 2 liebig based pots and the 'Blockhead' 60K btu propane heat
stillvodka
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Re: copper pot still clean up

Post by stillvodka »

Usge wrote:Lemon/salt will absolutely strip copper down nekid. I've heard of using it on the "outside" but ain't never heard of using it on the inside. Other than that, I'm sure it works! (ie..down to the shiny copper metal). Dunder, and others, have said just use hot-slops from a stripping run to soak it. I know that sure enough makes the bottom of my pot clean after a stripping run.

Using vinegar and or vinegar/water soak was also something recommended, and something Iv'e used. But a friend of mine who's a plumber, and whos also familiar with distilling, suggested that the copper could absorb the vinegar and it could eventually ruin your still (ie., could give off-tastes). He also said lemon salt used all the time would just eat your still away to nothing. Since then, I've used only water to flush out my still and I can definetly tell my still heads need some cleaning.

Seems to me, it makes sense that if copper is absorbing some of the bad stuff that over time it would start imparting off-tastes to your distillate. And it makes sense that something that strips it down to bare copper would be the surest way to do that. I just recall from somewhere, can't remember where, being specifically warned "against" using lemon/salt on the inside. And my plumber/distiller friend has said vinegar would permeate the copper and ruin it (for flavor/taste). I guess that leaves the tried and true "hot slops" method.


Just wondering outloud if anybody who's used any of these various methods of cleaning has noticed any off-tastes or other issues develop over time?
I have never used any of these methods for clean ups on copper, I know that Acid can destroy lots of thing , but surly it can come down to what sort of Mix/ Ratio of the cleaning solution you make up and how long it's left in contact with what you are trying to clean.
Usge
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Re: copper pot still clean up

Post by Usge »

So, nobody actually uses any of these methods beyond an initial cleanup. Hmmm. I've been using just water rinse too, and I feel it's not doing good enough job. Overtime, crap has built up on the copper in the top of the still heads (yellow, orange, green) and I think it's giving off-tastes at this point. Trying to use water to clean it out hasn't helped. Reckon I'll try hotslops.

I also recall another (similar) method recommened by Ian Smiley in his book chapter on making pure ethanol. He suggests rinsing all parts of the still before "every" run, using 3 Tblspoons of citric acid to 1 gal of water. (pot, column, tubes, everything). Then rinsing out the solution with hot-water. Sounds similar to the lemon/salt rinse.
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Re: copper pot still clean up

Post by Bsnapshot »

Is it OK when you clean up after a run with hot slop but do not use your rig for a month or so to leave the green patina
in the column? Or should that all be cleaned out before your next run down to the copper?
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zymos
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Re: copper pot still clean up

Post by zymos »

[quote="Usge"

Seems to me, it makes sense that if copper is absorbing some of the bad stuff that over time it would start imparting off-tastes to your distillate. And it makes sense that something that strips it down to bare copper would be the surest way to do that. [/quote]

That's not really what is happening though. Copper is acting as a catalyst to oxidize sulfur compounds. It isn't absorbing them-they are still there, they just aren't stinky anymore.

The kind of mild acids we are talking about here-citric, lemon juice, vinegar, would take forever to remove enough copper to do damage to your still.
Usge
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Re: copper pot still clean up

Post by Usge »

Here's a thread with more on the subject.

http://homedistiller.org/forum/viewtopic.php?f=1&t=9299" onclick="window.open(this.href);return false;" rel="nofollow
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