Burnt/Sticky Copper Still - 1st ever run

[Broadfield78]

Hi all. Complete newbie here - have been reading the forum for ages now and learning as much as I can. I have a small 2.5 litre copper alembic still

Today was finally the day that I was brave enough to switch it on! Got everything set up safely and knew what I was going to do - filled it with 0.5l of deionised water and switched on the heat

When the temp got up to 70 degrees or so it started to smell like burning. As I’m only using water (as a practice) I continued as didn’t think anything would be able to burn. After completing the run and letting everything cool (I didn’t boil dry, I left about 100ml in the boiler) the bottom of the copper pot feels sticky. Inside the pot there is slight discolouration of the copper base and a copper of what look like scorch marks

What did I do wrong/should I be worried - or is this just normal for the first run or two using a new copper still?

[MooseMan]

Ok, so have you done a vinegar run on the still, followed by a sacrificial alcohol run?

These are both required to clean the still before anything else.

[8Ball]

Read some more about sacrificial runs to break in a new boiler. Thats probably residual soldering flux you are seeing.

[AlZilla]

If you didn't do any cleaning before you ran it, it's entirely possible that a new copper still might be coated with something to keep it from tarnishing, lacquer or something.

Copper is going to discolor a bit when you heat it enough, anyway. A couple of pictures might be worth a thousand words.

I think you can be forgiven for assuming it's ok to practice boiling water in something meant to boil water.

In case you don't know, copper cleans up easily. Star San solution or something you make yourself called "551" from 500 ml water, 50 ml hydrogen peroxide and 1 ounce of citric acid.

Welcome aboard and good luck.

[Broadfield78]

Thank you all for your replies. It is much appreciated

I haven’t done a vinegar run yet - I stupidly thought I would practice with just deionised water for the first run to get used to controlling the temperature etc. surely I couldn’t mess that up! But it seems I did. I shall certainly do the vinegar run next and then a sacrificial run as suggested

If it helps here is a picture. I just want to make sure I haven’t caused any problems with what I have done so far!

[MooseMan]

Thank you all for your replies. It is much appreciated

I haven’t done a vinegar run yet - I stupidly thought I would practice with just deionised water for the first run to get used to controlling the temperature etc. surely I couldn’t mess that up! But it seems I did. I shall certainly do the vinegar run next and then a sacrificial run as suggested

If it helps here is a picture. I just want to make sure I haven’t caused any problems with what I have done so far!

Yes that's probably just residual flux or possibly machining oil that you've cooked onto the base, nothing to panic over.

If you have a copper scrubbie, give it a bit of a scrub in there with some soapy water to get most of the crap off.
I'd advise at least 3/4 of a boiler full for the vinegar run, a good long run and if you have any small bits of copper scrap you could drop into the pot that will help to scour the base clean and save you some scrubbing.

As soon as that's done give it all a really good hot water soak then lots of hot water flushed through everything to get the acid out, then whenever you can, do a sacrificial alcohol run.

[contrahead]

It might be 'your' first run, but you didn't specify if your tiny copper alembic had been used by a previous owner, or not. That might not be corrosion or flux; hard to say. It could be a built up patina from previous use; possibly. And why is the center at the bottom silvery looking?

My first still used a boiler that was actually just a stainless steel Presto pressure cooker. Small capacity, just 3.78 L. My usual procedure involved making multiple stripping runs before making a final spirit run. After time, an ugly orange brown (copper colored) patina would be built up inside the pot. The patina(s) were stubborn and could not be removed by soap and steel wool. I discovered though, that merely by adding spoon of baking soda, at the beginning of a spirit run, this problem could be solved. The spirit and pot would be clean but the spent wash came out a dirty brown. Try some baking soda maybe.

[Broadfield78]

Thanks for the further replies. The still is brand new so never been run before. I too was a bit worried by the fact the base looks silvery and wasn’t sure if that was normal!

I shall follow the good advice here and have a clean up, then a vinegar wash run, and then a sacrificial run and fingers crossed I’ll be good to go by that point!

[jonnys_spirit]

Here’s the bottom of a well used cooper pot still.

Like others have suggested - do a vinegar run then a sacrificial or seasoning run. Rinse with water after each use. No need to scrub and clean regularly. A strip run is lower abv in the boiler and is slightly acidic- a spirit run is boiling ethanol for several hours. Both of those activities “clean” the still quite well. A patina will develop (not verdigris) and that’s a good thing.

Also not sure about the silvery bottom that has become exposed. You may want to check with the manufacturer about that.

Cheers!
-jonny

[MooseMan]

I didn't want to confuse matters by mentioning the silver look to the base, but it's quite possible that a stainless base plate has been riveted in to the bottom of the still.
You'll see for sure once it's all clean anyway.

[Broadfield78]

Thank you everyone for taking time to help me out - I really appreciate it

[MooseMan]

Very welcome, let us know how it goes when you're done cleaning anyhow.

[Broadfield78]

Very welcome, let us know how it goes when you're done cleaning anyhow.

The baking soda worked a treat to bring the copper back from that silver shade I was seeing.

Did the vinegar run this morning and some new funky colours have appeared in the bottom (well different shades of copper I guess rather than colours). Have had a good rinse out, another baking soda application and feel ready to give the sacrificial run a go next time

On that note - any recommendations for how much I should put in my 2.5l still for that? Would 0.5litre at 40% be ok or should I be looking at a greater volume?

[MooseMan]

That's very good news, glad to hear it.

Your half litre should be fine, add plenty of water to get it to 2l and you'll have lots of volume then, to have time to play with your condenser water flow etc, use it as practice while you can!

[Demy]

Very welcome, let us know how it goes when you're done cleaning anyhow.

The baking soda worked a treat to bring the copper back from that silver shade I was seeing.

Did the vinegar run this morning and some new funky colours have appeared in the bottom (well different shades of copper I guess rather than colours). Have had a good rinse out, another baking soda application and feel ready to give the sacrificial run a go next time

On that note - any recommendations for how much I should put in my 2.5l still for that? Would 0.5litre at 40% be ok or should I be looking at a greater volume?

I would think of something like 1 litre....you have to consider that not everything will be extracted (the boiler does not have to be emptied 100%) and it has to flow enough to get a good cleaning. I also recommend pre-cleaning where your hands reach...

[AlZilla]

Broadfield78, what's your heat source and how thick is that bottom?

I'm thinking maybe it's a hot plate or some such and you're running it hot. If the bottom is thin, I could see that causing discoloration on the bottom. Those marks in the first pic look a bit circular.

Just curious, really.

[AlZilla]

Very welcome, let us know how it goes when you're done cleaning anyhow.

The baking soda worked a treat to bring the copper back from that silver shade I was seeing.

Did the vinegar run this morning and some new funky colours have appeared in the bottom (well different shades of copper I guess rather than colours). Have had a good rinse out, another baking soda application and feel ready to give the sacrificial run a go next time

On that note - any recommendations for how much I should put in my 2.5l still for that? Would 0.5litre at 40% be ok or should I be looking at a greater volume?

I'd fill it 1/2 way, at least. You really don't need 40%, either. 10% should be more than enough. (maybe one of the pros around here will correct me on that, given the small size of the still?)