temperature for potstill

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

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T-type
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temperature for potstill

Post by T-type »

Im wondering how you guys judge how you run. I hear you guys talking about a pencil sized constant flow or a drip per second? now is the pencil sized stream for like stripping runs? and the drip per second for final distillation or first time distillation and running it real slow?
I guess it's ganna take practice and getting used to my still.
theholymackerel
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Re: temperature for potstill

Post by theholymackerel »

I run a strippin' run as fast as I can.

On a spirit run I slow it way down to a pencil-lead sized stream. The right rate for you will depend on the size of yer wash/mash, it's ABV%, and the size of yer boiler and how well it's insulated.

If ya run a potstill too fast, or too slow, ya won't like yer results. Play with yer still and you'll learn it.
T-type
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Re: temperature for potstill

Post by T-type »

How long does it usually take someone with a potstill for 25liter wash to distill? needing to know this just for comparing if i run it to slow.
I shouldnt play with the temp that much then? and after i get it to a boil switch it over with my router speed control for medium heat or so to keep it boiling.
Should i watch the vapor temp that close with my potstill? or go by the distillate stream?

seems like im running it slow taking 8 hours or so and not even getting to the tails with dwwg, with only a drip or so a second.
still is a 7.75 gallon keg with 2" x 18" stainless column and liebig condensor.
theholymackerel
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Re: temperature for potstill

Post by theholymackerel »

atjones44 wrote:seems like im running it slow taking 8 hours or so and not even getting to the tails with dwwg, with only a drip or so a second.
Yep. A drip a second for a potstill is too slow. That might be ok for a small column still that isn't super efficient, but a potstill has gotta be run faster than that.
T-type
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Re: temperature for potstill

Post by T-type »

How long does it take you to run a 25l batch?
punkin
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Re: temperature for potstill

Post by punkin »

I find a rate of 4litres (just over a gallon) an hour to be about right on a stripped low wine spirit run. You should only need the slightest heat input to render this speed, just ticking the boil over. Some might run a little slower than this, depending on the diameter of you're lyne arm and condensor.

You're product will not be all it can be running as slowly as you are, not to mention getting your Saturday back :mrgreen:
T-type
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Re: temperature for potstill

Post by T-type »

No kidding about that whole day being gone. lyne arm and condensor are 1/2" stainless with 3/4" stainless water jacket.

You seriously get 4L in an hour and still keep the top of the column at 178-180+ f? its only my second run so i still dont quite know my still all that well...i think i was fiddling with my router speed controller in keeping my element or vapour at the right temp....maybe i should leave it alone on a medium setting after it reaches a boil and it'll even itself out.

because i was getting 80% abv on my first distillation on my pot column from my dwwg. turn up the heat and maybe it'll even itself out in the column i hope
punkin
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Re: temperature for potstill

Post by punkin »

It'll help you a lot if you just stop looking at or thinking about temperature.

Concentrate instead on distillate strength (abv) and taste and smell.

Potstilling is a craft, not a science.


Yes i seriously get what i say i get. 1" lyne and punkindensor, but Gonzo used to consist of a 1/2" worm for the same outputs.
T-type
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Re: temperature for potstill

Post by T-type »

i'll try my next run with testing abv/taste and smell instead of trying to keep the vapor temp just right. I think i was thinking "it has to be perfectly at 78 celcius" and at that temp i hardly got 1 drip a second...
bourbonbob
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Re: temperature for potstill

Post by bourbonbob »

I don't use a thermometer on my pot, I use an alco meter. I have a 50 litre pot and I strip about 5 litres per hour, comes of at about 130 proof, when I do spirit runs it comes off at 190 proof.
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rad14701
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Re: temperature for potstill

Post by rad14701 »

atjones44, it sounds like you've learned the frustration of chasing the thermometer on a pot still... With a pot still the temperature and ABV change throughout the run due to the alcohol:water ratio in the boiler changing as the alcohol is depleted... This is the biggest difference between running a pot still versus a reflux still... A reflux still reaches and maintains an equilibrium which a pot still never attains...

Try your next run without the thermometer because then you'll have to pay closer attention to the other indicators throughout the process... Good luck...
T-type
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Re: temperature for potstill

Post by T-type »

thank you guys i will try without the thermometer, rely on my other senses.
blanikdog
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Re: temperature for potstill

Post by blanikdog »

atjones44 wrote:thank you guys i will try without the thermometer, rely on my other senses.

You will find that that's the best decision you will ever have made as a potstiller, atj.

blanik
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(50 litre, propane heated pot still. Coil in bucket condenser - No thermometer, No carbon)
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Hawke
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Re: temperature for potstill

Post by Hawke »

I can strip at a little over 2 gallons an hour. (2" into 3/4 liebig) Still working on slowing down the spirit run. (May need to get a smaller burner)
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
tracker0945
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Re: temperature for potstill

Post by tracker0945 »

Just for the record I will say this loud and clear. I use a thermometer on my pot still.
There, I said it and I feel much better now.
I do not use it to tell me how fast to run my still, I use it as a guide to let me know when to expect the change from hearts to tails etc. as I find it easier to use that rather than trying to read a bouncing hydrometer in a parrot and converting readings with temperature conversion.
Anyway back to the original point.
Use your thermostat heat control to produce a thin stream of distillate, no matter what your THERMOMETER OR HYDROMETER tells you.
After a run or two, try some different speeds. Your taste buds will tell you what is the best speed to run your particular outfit


Cheers and good luck.
2"x38" Bok mini and
Pot still with Leibig on 45 litre boiler
Usge
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Re: temperature for potstill

Post by Usge »

Just my 2 cents: Every still, given the same heat, etc., is going to output different too, therefore, time takes to run is going to be relative too. So, you have to find the right spot for your given still. You can only do/know that by running it faster, test results. Run it slower, test results. (as mentioned above)

On my alembic, which is free flowing, has nice open lynearm per it's size, etc., reducing heat results in a small stream. I "can" lower it to just a drip, but doing so seems to bring over a lot of nasty stuff. Time for a spirit run on this still is about 3.5-4hours hours and it produces a very smooth, blended spirit from all that comes over. If I run it very slow, to the point of "drip", it produces a much harsher spirit that doesn't blend out well.

On my gooseneck head, the lynearm is somewhat restricted for it's size. Reducing heat will fast drip and trying to push it faster than that will pull tails. It takes about 6 hours to do a spirit run. Running it to slow usually makes things nasty (brings over lots of higher/lower alcs that sting and burn and etc). Running a spirit run too fast (too much heat ) just pulls tails early. Spirit run on this head takes me about 6 hours and will produce the same output bell curve as the alembic where there is a long transition/fade of heads to a couple of clean jars in the middle, then fade to tails on out. Out of 13 jars, there will be 6 before it gets completely clean. The 7th and 8th will be completely clean/sweet/hearts. Then you start to hint at "bourbony" flavor coming in, which grows stronger until it looses it's sweetness...and you get stanky tails, followed by watery ones. This is the same basic output curve as the smaller alembic...just using bigger jars to collect in. Running this head is very similar to the alembic. It also seems to produce more higher/lower alcs (stinging, burning, harsh, etc.) if you run it at a drip instead of a small stream on a spirit run—ie..you run it too slow.

On my rocket/reflux hybrid head (on the same pot), you can't even do a strip run with it. The lyne arm is so restricted, and the vapor flow is held back by the liquid cooling vapor management system. It "only" drips no matter what heat you apply. If you run too much heat..it will just drip faster and pull heads. It takes 11-13 hours to do a spirit run on this head. On this head...you "want' to run it slow with lots of cooling. It will produce a clean/sweet spirit, but at higher abv. Its not as high/efficient as some of the results I've seen posted for VM or other types of reflux stills (it won't do 90%). But, it's sort of in between....not a vodka type/neutral, but cleaner than a standard potstill head. It also tends to run more like a pot with thumper in terms of output...given it tends to settle in and hold higher abv throughout the run..the fall off quickly towards the end. Gives you more "middle" to play with. So, I actually like the results I get from this head (mostly), it just is a PITA to run it. On a 12 hour run, using 15 jars..I'll usually start getting clean middle about the 5th or 6th jar (jars before are very sweet, but still hint at heads) that will hold for 4 or 5 jars, before starting to pick up slight tails...still sweet. Which it will hold for another 3 jars or so before it quickly goes into deep tails.
T-type
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Re: temperature for potstill

Post by T-type »

Nice explenation. Thank you
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