My first rum run and a query on temperature

Many like to post about a first successful ferment (or first all grain mash), or first still built/bought or first good run of the still. Tell us about all of these great times here.
Pics are VERY welcome, we drool over pretty copper 8)

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Chill Bill
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My first rum run and a query on temperature

Post by Chill Bill »

Just distilled my first batch of rum

The wash was 20L
3kg raw sugar
3kg blackstrap molasses
Bakers yeast

I have a 10L copper alembic pot still,
so I poured in half the wash (after fermenting for 7 days)
and came across something I thought was well, weird.

Methanol and nasty stuff came out at 58 - 75 degrees celcius
Once the still hit 78 (temp for ethanol)I turned the hotplate down and maintained that temp,
But nothing more than a drop every 20 seconds,
So after patiently waiting and waiting, I let the still steadily move up to 81 degrees celcius
Still nothing, so far an hour and a half passed and no more than 100mL
As the still creeped up to 82 degrees, (temp for 2-propanol) it starts coming out at 4-5 drops per second
Over the time of the still going from 82 - 88 degrees (til when I shut down),
The still produced about 1.5 Litres of nice smelling rum.

Now down to the question
Shouldn't the still be producing more at 78 degrees?
Does this mean the run came out all as tails?
What's going on here?
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NZChris
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Re: My first rum run and a query on temperature

Post by NZChris »

There is nothing weird about it. You just haven't spent enough time studying the subject.

Tape over the thermometer so that you can't read it and run it watching the output stream.

What worries me, is what else you don't know. E'g. Have you done cleaning runs with vinegar, then alcohol to get rid of any flux and machine oils that can make you severely ill?
Chill Bill
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Re: My first rum run and a query on temperature

Post by Chill Bill »

Yes of course, this is the first time using the still AFTER a thorough scrub, vinegar run, scrub and alcohol run.
The way I understand it is ethanol should come through at 78 degrees, no?
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Still Life
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Re: My first rum run and a query on temperature

Post by Still Life »

No. That's why NZChris said to cover that thermometer.
The temperature is a moving target.
Sorry to say, but you've fallen into the "Magic Temperature" trap.

You get what you get when the still decides to give it to you.

Here's some lengthy, but quality spoonfeed reading to bring you up to speed: http://ww.homedistiller.org/forum/viewt ... 15&t=52975
Pikey
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Re: My first rum run and a query on temperature

Post by Pikey »

Where are you measuing the temperature ?

You run the still - collecting in small jars until the abv of your product is not worthwhile any more.

It is counter - intuitive and goes against all the theory you've obviously gone to the effort to look up and work out.

Next time you'lll know what to expect and will hopefully run it longer (as I did at the beginning) - You'll get there now you have done one.

Respect mate - for trying to do it "Scientific" - sadly in the world of azeotropes and "Affinities" - it just doesn't work like that - but think on't - if it DID work like that - you wouldn't get "Rum" out of the pipe - you'd get unflavoured motor fuel !
Chill Bill
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Re: My first rum run and a query on temperature

Post by Chill Bill »

I guess this comes down to 'knowing your still' as all stills would operate differently.
I'm reading temperature from an inbuilt thermometer in the Vapour path, above the pot.
I have collected in 250mL jars, I guess my next step is to find % of each jar and I can work from there.
Thanks for clearing that up guys!
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Saltbush Bill
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Re: My first rum run and a query on temperature

Post by Saltbush Bill »

The best advice you have had in this thread is to tape over the thermometer and not look at it again.
A thermometer will just confuse hell out of you on a pot type still.
Learn to drive your still by the output speed from the spout.
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Yummyrum
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Re: My first rum run and a query on temperature

Post by Yummyrum »

+1 Salty

Chill bill , you are absolutely correct that Ethanol boils at 78.3 degC ..... but that is pure Ethanol .

Pure water boils at 100 deg C .

If you mix them together they are no longer pure ... they are chemically bonded together and the boiling point will be somewhere between the two temperatures depending on the proportion of each .

You can not as you found out seperate out the Ethanol by holding at its pure state boiling point .
When the mixture is boiling both Ethanol and Water ( and other stuff in the wash ) will vapourize leaving some of the water in the boiling state .The change from liquid to gas state is called a phase change and it is during the phase change that some of the water bonds are broken .

If you condense that vapour and then boil it again , it will have a lower boiling point than the first time be ause ther is less water in it now . Again it will vapourize the Ethanol will boil off with some water and other stuff again leaving some water behind .

This is why we double or tripple distill or use reflux stills to get a higher purity of Ethanol which can't ever be done in a single pot still distillation

Edit thanks Pikey , I have fixed that typo :shh:
Last edited by Yummyrum on Sat Jun 10, 2017 8:23 pm, edited 6 times in total.
Pikey
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Re: My first rum run and a query on temperature

Post by Pikey »

Chill Bill wrote:I guess this comes down to 'knowing your still' as all stills would operate differently.
I'm reading temperature from an inbuilt thermometer in the Vapour path, above the pot.
I have collected in 250mL jars, I guess my next step is to find % of each jar and I can work from there.
Thanks for clearing that up guys!
Yes stills operate differently and thermometers are a tool the same as any other. I get some flack on this site for running two thermos, but again think about it. If you were running water, your thermo would measure 100 or thereabouts. What you are measuring is the "Average" temp of the mix of ethanol and water in your vapour. - A bit like a hydrometer measures the "average SG of the ethanol, sugar and water to give a reading.

Until your temp gets up around the 100 mark, if you switch off you're leaving ethanol in the pot !

WIth a small pot like that, I'd be inclined to take 100 - 150 ml jars - certainly for the 1st half litre and the last litre and a half or so.

You should measure the abv's of the jars - as you go until you get the "Feel" of it - the abv's go down pretty quick and those last ones will be fairly low (or they would be if you'd taken all the ethanol out of the wash) :wink:

I use a permanent marker pen and write the number of the jar and abv on the side of the jar - helps a lot later when you come to make cuts - and your foreshots can be used twith a kitchen towel to wipe the markings off after.

There's some truth in what Yummy says - but some of us don't do double or triple distils - but 1.5's - where the heads and tails go back in the pot with the next wash and the suts we decide to keep are - well - kept !

What ab v's are you hitting ?

;Edit - yummy - with more ethanol, the boil point will be lower rather than higher - I believe - I know it's a typo but needs clarifying for the lad. 8) ]
Chill Bill
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Re: My first rum run and a query on temperature

Post by Chill Bill »

From jars 1-6 (after removing foreshots)
1- 70%
2- 65%
3- 62%
4- 58%
5- 53%
6- 48%
Pikey
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Re: My first rum run and a query on temperature

Post by Pikey »

Not too bad - but as you can see - a lot of jars missing off the end - You'll get 'em next time :thumbup:
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NZChris
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Re: My first rum run and a query on temperature

Post by NZChris »

To make decent rum with a copper alembic, you really need to double distill it. For many of us, this means collecting until the whole collection is around 25-35% abv, then running it again. It is on this spirit run that you need to collect in jars for blending after airing overnight. You don't need a thermometer for this run either and if someone on a forum or youtube quotes you temperatures from their still, ignore them.

Once you have learned to run it without the thermometer, you can start using one to keep records that are specific to your still and the way you like to run it, although personally, I think a thermometer in the vapor is too affected by variables to be of much use, so mine is in the boiler charge, where it can be used to calculate the % abv of the remaining liquid.
Shine0n
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Re: My first rum run and a query on temperature

Post by Shine0n »

Now that you've got this run down, make another one and mix your all with the next wash
You'll get higher abv, better flavors and don't forget to collect in small jars.
Check abv of each, smell them, taste them (diluted) and feel them by rubbing the distillate between your fingers.

As mentioned, once you learn to drive your rig then you'll be able to use your thermometer but on a simple pot still you really don't need one unless you just want too for shits and giggles. Lol
If nothing else it will give you info about where your temp is at collecting at 100 ml at the time etc etc.

Once run rum is my favorite but that's just me, I do have a thumper though.

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nuntius01
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Re: My first rum run and a query on temperature

Post by nuntius01 »

im a little late on the reply, but i only use my temp gauges as a rough indicator. remember they are just a tool. i have them in my pot at the top of my column and on my thumper. knowing how your still runs will be much more beneficial than watching the temp gauge. i use mine to essentially tell me how the vapor is ,moving through my still. although i dont really need them for that it is convenient and gives me something else to write in my journal with every run i make. so, bottom line is, learn your still. if the temp guages help you understand how it runs great. but dont rely on them. good luck
I'm just the bank and the mule

post your still pics here
http://homedistiller.org/forum/viewtopi ... 16&t=66917
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