Pot run: how low and how slow?

[John Barleycorn]

I decided to do a pot run with a PSII HC (pot mode, no packing) and 20L of Rad's All Bran wash at about 11%. Using a 1500w plate with router speed controller. Up until now, I've been simply stripping, running as hard and fast as I can, to build up my low wines. But I decided to try a pot run to see what that's all about.

In any case, I've read a lot about running "low and slow" and came across quite a few subjective descriptions like, "a slow tickle", etc. Since I have a "numbers" personality, can anyone share their typical collection rates when they're running low and slow on a pot run?

I slowed things down to about 250 mL/hour. On my rig this was about 1 drip/sec. The good part was I had plenty of time to observe, take notes, smell, taste, etc. -- very cool -- it was textbook all the way. The bad part was it took a very long time. When I strip everything gets smeared, which is fine since I'm just saving up for a reflux run. But I decided that I was actually very impressed with the result of the pot run, so I'm looking for some numbers guidance in case I get that itch again (but don't have as much time to spend).

Thanks,
--JB

[blind drunk]

Try 1-1.5 liters per hour or even a little higher. 1 cup an hour is too slow. Should be a broken stream or a steady stream. There's a sweet spot somewhere between. Others will chime in.

[Usge]

JB, you are doing the right thing (experiment) and see for yourself!! Take notes, etc. All good You were running about as slow as you can and still have something come out. 250ml/60min = 4.2ml per min. The reason you don't see much definitive info like that is because it can vary still to still not to mention peoples preference. Some people can get the same separation running faster..some slower. And the taste can vary depending upon how you run it. The important part is that "you" find the sweet spot that you like.

Save a small sample of it. Then throw it all back in the pot, and run it again faster to see what kind of changes occur. I generally like to make the differences apparent when doing a comparison like that..so I would run heat just till it breaks a stream. This generally works out somwhere around 20-35ml per min. Some stills with larger volume still charges might run higher than that (say up to around 40-50ml per min range. But, this is close enough to give you some idea.

Running faster will change the flavor a bit. It will smear more of it together and the flavors from the back side of the run (towards tails) that have more "grain" flavor will come through sooner. HINT: Nobody says you have to run it same speed all the way through either. Some people run it slow up front to get better sepration off the heads..then speed it up some through hearts to get a nice blend...then back it back down when they taste tails side coming until they've collected all the hearts....then raise up heat full and flush out tails.

Since you've had a good slow run...do the 2nd one faster (all the way through) just to note the differences. After it starts to drip and pickup...adjust heat until it just breaks into a stream (ie., if you back the heat down..the stream will bobble and dribble). Let it run like that at that heat seating all the way through. Don't adjust it. Note what happens when it starts and stops. At some point it wont' hold a stream anymore. The stream will sound heavy in dribbles...(tails). The distillate from this run should have a heavier flavor profile than your previous light runs. You may prefer one over the other. Running faster tends to add more tails side flavors — ie, it pulls them more towards the middle. Finding the sweet spot where it all tastes good to you is what is important to do. And "yes" running slow takes longer. But, if you like the results....can't beat it.

[blind drunk]

Too add, when I run too slow, I find the blending really difficult. The jars are too distinct and I stumble around not knowing what to do. The "middle" jars, for example, is too clean. I try and figure out a speed whereby the transitions are not as distinct and the middle parts seem to have the best of all the parts. I see it as a controlled smearing, in my mind's eye. You can also try insulating your column and see if you like the results. That's what I've done and I haven't looked back since, so far anyways. It's alot of fun, good luck.

[Usge]

+1 BD

[John Barleycorn]

Thanks gentlemen -- that's what I wanted to hear ... and what I _needed_ to hear.

I was a snipe when I was in the service, so I had the privilege of operating all the fun gizmos & gadgets that made up a steam main propulsion plant. If you understood how things worked, knew your lines & valves, and understood the numbers from the gauges, you could have a helluva lot of fun. Everything was based on repetition and technique to get as close as possible to perfect execution. Which may be why neutrals appeal to me. It was like playing football: master your techniques and reads & it's worth the time ... you'll have fun.

The subjective part of pot stilling is however ... well ... so damned subjective . I can now see why it takes so much time, practice and repetition to master. The artistic part of things has been a lifelong struggle ... sometimes satisfying ... but man, I really have to work twice as hard as the other guys. So refluxing is more of a natural fit for me. But like I mentioned in my initial post, I was curious and so gave pot stilling a whirl. I'm glad I did. I'll have to dabble some more as time permits.

Again, thanks for the great guidance,
--JB

[King Of Hearts]

Hey JB, I run a simple 2 inch SS pot still head from Brehaus. This is from a ten gal 8% mash of 60% corn, 20% wheat malt or rye malt and 20% distillers malt.I put one copper scrubby in the middle of the column. I strip and get 2 gal. of 35%. I raise it up slow. On the second run or spirit run I find 2-3 drips per second works for me. It comes out cool to touch. The temp at the lynne arm is 172'. After 150-200 ml foreshots I get 1 liter heads 2 liters hearts and 1 liter tails. This takes about 8 hours.

[dakotasnake]

i guess in a nutshell after you run your still enuff you'll no it better than your mother-inlaw. i no what its gonna do b4 it does-- untill you change sumthing [ recipe, heat, add or subtract sumthing on the still] than you'll adjust. on my potstill a toothpick size stream nets the best results when i plan on a single run. b4 i cut 6'' off my riser 3 or 4 drops per sec. was best. just run it alot an stock up for next winter.

[ozarkbill]

I have run my PRO II pot still fast and slow. 2-3 drips per sec is perfect for me as far as taste. It is hard at first to not bump the heat to get done sooner but if you want good product you need to do it right. Two 6 gal runs takes me 6-8 hours and I run to about 130-140 abv and after airing blend to taste and proof I want. My magic proof number seems to be 83-85 proof measured with an alcoholmeter. I keep some Jack Danial's black and taste to this as close as possible, It is always sharper tasting than the JD's but the aging brings it into line.. Then add 3-4 drops of maple syrup per QT and wait, on charred oak sticks, 3 months or more. Ozarks sipping whiskey fur sure...

[King Of Hearts]

Part of the fun is figuring out how to run it, just takes patience and practice.

[rtalbigr]

I actually judge my output rate more by the sound of the bubble breakers in the bottom of my pot than the out put stream. If I can hear them bouncing then I'll turn the heat down until I can't hear them anymore. Of course, I've done so many runs I know where to set the heat control. When I get deeper into the hearts I might turn the heat up slightly, depending on what I'm running. Once I get into tails I'll turn the heat on up to 3/4 power and just let it run on out.

Doing it this way I'll get an output that a very thin but steady stream to a broken stream.

Big R

[RumBrewer]

Sucks that we can't just have a mentor system.
I would sure like to help some of you guys prepare a solid wash, and I'd love to have a master shiner come and show me (ON MY STILL) how to run the damn thing. Took me 3 years to figure out the old one, who knows how long it'll take with the new one.

[Usge]

Every still could be different (although there are some common sizes around as well). I had a still had a big head but a 3/8" lynearm...you had to drip that thing off "s-l-o-w" to get anything that wasn't smeared to death with tails. My 2" lynearm that necks down to 1/2" by contrast finds happiness somewhere faster (up to a small stream). No accounting for taste either...some people like flavor of slow-single run on a pot. Nothing wrong with any of it, despite what consensus may be. Just what you like. So, it's very hard to say...."this is how you do it" other than the basic logistics of operation. Yes..this is how you do it till you experiment and find what you like and where your still performs best for you. That's it.

The main thing is to TRY it different ways. I bet there are plenty of people here who started out by adjusting their output/heat to a small stream (cause that's what consensus says) and never looked back. Run it slow one time. Real slow. See how it changes things. Hell you might find you like it better. Or you might just confirm your getting the better out of it running the way you are. If you are a drip-drip-drip potstiller...try wicking it up to a stream and let it run. See how it differs from your normal runs.

You "will" get more separation running slower in general. But, separation (and concentration) of "what" is the question. Well, ethanol of course to some degree....you'll find not so much abv jump running one way or the other. Its the other things that come along with ethanol for the ride that you need to be concerned with — impurities that compound with it that make up the flavors. If that ends up being things that taste good when concentrated more.....running slower will benefit you. If those previously subtle flavor compounds concentrated and isolated end up tasting like "crap" .....you aren't going to be so thrilled. Pot's aren't made for clean separation. They are made for "blending" things. So, run it however best "Blends" the flavors you have, into what you want. Might take some experimenting...but it will be worth while. You might want to get a few runs under your belt first using consistent procedures just to have a baseline to work from.

[Tater]

Sucks that we can't just have a mentor system.
I would sure like to help some of you guys prepare a solid wash, and I'd love to have a master shiner come and show me (ON MY STILL) how to run the damn thing. Took me 3 years to figure out the old one, who knows how long it'll take with the new one.

Id think a experienced stiller could dial in on another still quicker than a newbie .However he would still have to learn to drive it.

[Fourway]

Too add, when I run too slow, I find the blending really difficult. The jars are too distinct and I stumble around not knowing what to do. The "middle" jars, for example, is too clean. I try and figure out a speed whereby the transitions are not as distinct and the middle parts seem to have the best of all the parts. I see it as a controlled smearing, in my mind's eye. You can also try insulating your column and see if you like the results. That's what I've done and I haven't looked back since, so far anyways. It's alot of fun, good luck.

^^^^
this


When I wind up with really distinct fractions the full weight of my ability to become badly discombobulated kicks in when I start trying to blend flavor back into the flat heart...
I start doubting my labels... getting confused about what I just smelled and why did I smell it here but not here but here again two jars away.
I have much much better results running for something that pleases me across a larger portion of the cook than winding up with a bunch of portions that either dont impress me or make me think bad thoughts.
Its still low and slow... but when you get down to the drips range that tends to be too slow for me. I want a twist I can watch.

[Tater]

When running my pot I like to see the twist also.Dialed in right can tell heads are almost gone when stream paused slows and picks back up. .On washes that contain sugar or 2nd run of them that don't. There is a slight rattle of copper pieces breaking the boil.Nice beads forming as product hits bottom of jar.Sounding kinda like rain. Damn I love stillin .

[John Barleycorn]

There is a slight rattle of copper
pieces breaking the boil.
Nice beads forming
as product hits bottom of jar.
Sounding kinda like rain.

Very poetic. Sounds a bit like Henry Wadsworth Longfellow!

[Stout8174asheNC]

I have a 3 gallon vexar pot still. Thumper. Condenser. Etc. all from Amazon. Lol
This time around I’ve turned my heat down a lil. Taking longer. But flavor is there. Honestly. I just picked up this hobby for 1st time in 20 years. I’m hooked again. I love the science of it all. On the other hand. 5 runs now. Haven’t been impressed yet. Many many notes. Basically same mash. I’ve adjusted. Sugar,yeast, my grains accordingly. Trying to find my sweet spot.

[Swedish Pride]

I have a 3 gallon vexar pot still. Thumper. Condenser. Etc. all from Amazon. Lol
This time around I’ve turned my heat down a lil. Taking longer. But flavor is there. Honestly. I just picked up this hobby for 1st time in 20 years. I’m hooked again. I love the science of it all. On the other hand. 5 runs now. Haven’t been impressed yet. Many many notes. Basically same mash. I’ve adjusted. Sugar,yeast, my grains accordingly. Trying to find my sweet spot.

Do you do single runs or one and done?
Strip until you have 3 gallons of low wines and then do a spirit run , this will help with the quality of the product

How fast do you run?
The smaller the diameter of your riser the higher the vapour speed .
Higher vapour speed means less separation of the fractions.
So small diameter riser needs to be run slower than a wide diameter riser

How do you do your cuts?
Cuts are more challenging on a put run so put in a lot of time sampling the collected spirit.
Try to collect in 20 jars or more as you are learning , I think that's about 5oz per jar with a full charge or low wines in your boiler.

This is all based on potty only, I've no experience with a thumper.
My reading tells me the same holds true with a thumper, it's not a magical "one and done" tool.

Hope this helps somewhat

[Yummyrum]

The smaller the diameter of your riser the higher the vapour speed .
Higher vapour speed means less separation of the fractions.
So small diameter riser needs to be run slower than a wide diameter riser

Not so sure about all that Swedish .

But this is a good question

How fast do you run?

It is all about how long it takes you to distill your boiler full . 6-8hrs should see you in the golden zone
O
The smaller the diameter of your riser the higher the vapour speed .

Yeah , thats a fact . Vapour will travel faster though a small pipe and slower through a larger diameter pipe.

Higher vapour speed means less separation of the fractions.

Not sure exactly what you are coming at here .
My understanding is Separation of fractions happens in the boiler . The power (heat energy ) will liberate the fraction and it will leave the boil as vapour .

Now , liberated as vapour , its speed will vary depending on the size of the orifice it had to travel through …small tube , higher vapour speed ….. fat tube ….slow vapour speed ….. but it is still the same vapour that left the still .


OK , if you crank up the power to the boiler , you will
get higher vapour speed . But in this case , the lower separation is not due to the higher vapour speed but rather because you excited the boiler and simultaneously released more fractions



So small diameter riser needs to be run slower than a wide diameter riser

Why ? The liberated vapour from the boiler will travel through a small diameter riser .

It will travel through it quicker than it will through a larger one . ……but travel through it , it will .

So now we get to the limits .Power 1, 2 ….5 …. 10kw. More… what is too much power ?

What constitutes a small size riser ? Is it a 1/2” ……or less ? 1/4” is stupid small but it is about as stupid small as you could go … 2” is common . 4” is getting ridiculously big for home distilling .

OK trying to stick 10kw up a 1/2” riser is not going to work . It’s not because you won’t get separation in the boiler , it’s because it’s simply too much vapour trying to squeeze the heck through a skinny arse tube .


Which comes back to the point in question.

Separation of fractions in the boiler of a Pot still is determined by how much power you put in per litre .

Small charge , small amount of heat ( power)
Big charge , big amount if heat (Power)

The size of the riser will not affect the separation . It only effects the amount of power your still can physically handle .

[Swedish Pride]

That's my findings since going back running the potty again.

Used to smear like a bastard on my 1 inch potty.

Now I run my plater as a potty, no coolant to the reflux coil.
It's 3in at it most narrow section, before leibig but after keg.
Wider column makes for slower spread allowing the heavier compounds to fall back down the boiler again.
Or at least that's what I come up with if asked to explain why I get less smearing in the wider riser.

I believe there is seperation of fractions in the riser too not only in the boiler.
I've never been wrong in my life ever , would be odd if this was the first time

[NormandieStill]

I believe there is seperation of fractions in the riser too not only in the boiler.
I've never been wrong in my life ever , would be odd if this was the first time

My thought was always that if you have some reflux in the column then there'll be some separation there. I don't recall though if a vapour which is a mix of compounds has a single temperature at which the whole mix will condense or if certain constituents can be condensed out at different temperatures. I suspect that it's the former but...

Maybe your plated column is providing more passive reflux. Or maybe the slower vapour speed makes it easier for entrained compounds to fall back out.

It's all speculation on my part as I have a 2" riser feeding into a 16mm liebig and I don't do enough runs to be able to test the same low wines over two runs to see if it made a difference! I'm not often wrong either though... so who knows?

[Yummyrum]

That's my findings since going back running the potty again.

Used to smear like a bastard on my 1 inch potty.

Now I run my plater as a potty, no coolant to the reflux coil.
It's 3in at it most narrow section, before leibig but after keg.
Wider column makes for slower spread allowing the heavier compounds to fall back down the boiler again.
Or at least that's what I come up with if asked to explain why I get less smearing in the wider riser.

I believe there is seperation of fractions in the riser too not only in the boiler.
I've never been wrong in my life ever , would be odd if this was the first time

Doh , yes you would be correct Swedish . I had too many wines last night and forgot the Onion effect .
I guess it is fair to say that as your plater is actually made out of salad bowls IIRC ,in effect you have 3 Onions stacked together .

Posted with Normandie.

Even though the wash is boiling at a certain temp , the vapour liberated is not a single fraction but a mix of differing constituents .How hard the boil is will to a large degree provide separation but the vapour is never a singular fraction . Keeping the power low will help let the lighter fractions boil off first but there will always be a proportion of heavier ones coming off as well

Which is why the Deflegmator works on a Pot still . It is a Partial Condenser and will allow lighter fractions to pass while condensing heavier ones .
Large Risers can function as a Defleg .Passively cooled , they will allow some of the lighter fractions to pass while condensing some of the heavier ones . Not a perfect Defleg but possess some of the traits.

I do not fully understand Onions but I agree with you that the expansion and reduction of speed would allow time for heavier components to fall back . As well as providing some passive reflux.

[Swedish Pride]

Yeah, that's fair , I'll likely get more passive reflux than most other stills.

I'm to drunk to get I to a more elaborative answer so this is all you get

[Avalir]

Sounds like you've got a lot of detailed input, so I'll keep mine short and sweet.

I'm sure you've noticed the drip rate of the condenser fluctuates even at a set temperature. With better separation achieved at a slower drip, I'll aim to have defined droplets form until I'm safely in the hearts cut - if I ever see a stream/broken stream form at any point in the heads, I'll dial the temp down.
Once I'm in the hearts, unless I want a 24hr long spirit run, I'll raise the temp slightly so at it's fastest it reaches a broken stream.
Once I detect that taily aromas/flavors are making an appearance, I'll dial temp back down to where I have definable drips until I'm confident I'm beyond where I'd make my cut to bottle. From there, treat it like a strip run and blast the heat to collect feints and sweet water.

Sorry that didn't give you numbers to go by. I personally feel this hobby is more art than it is science and sometimes you just have to go with the flow. But an estimate on drops per second, I'd say in the heads mine ranges 1-3, hearts 5+/broken stream, and going into the tails 2-4.

I have once maintained a 1-3 rate for an entire spirit run. I will say those were the easiest cuts I've ever made; the tradeoff was manning a still for 32 hours. After aging, I'd argue you couldn't tell the difference in the quality of cuts vs how I normally do it; so unless you feel an extra 12+ hours of labor is worth the maybe half pint of product you'll salvage from the heads and tails cuts running a pot still, I'd advise not running quite so slow for the entirety of the run and you can still salvage that little bit of potential loss in a feints run.

[jonnys_spirit]

I have a small 2.5g alembic still with the "rotating top" riser and larger 16g boiler that I use an 18x3" riser into an "onion head" with a sight glass before the lyne arm and reducing down to a 2" shotty - both in pot still mode and I modified the alembic to use a 3/4" over 1/2" liebig...

The alembic "riser" is much wider that the larger still riser and I get a significantly higher proof out of the spout for longer... I can only assume that there's more passive reflux in that alembic system...

Empirical observations consistent over many runs in both systems..

Or as I like to think about it: "It's all about the molecules man!!"

In both cases I have gauged or measured the output and set the power so that my run will fill my "20 jars" over "6 hours"... The larger still has up to 5k5W via internal element and the smaller one uses a 1k5W hotplate... I sorta know where to set the knob now to get in that range so my measuring and science is less based on numbers and more shooting from the hip these days which I prefer - let the cards fall where they're gonna fall..

My take away is that the riser size does have an affect that is perhaps influenced by passive reflux and it's more pronounced in smaller systems with less power and larger height/width ratios... In the larger system the power tends to trend toward dwarfing the passive reflux potential or the differences between say 2" and 3" risers.. The difference between 2" and 4" is going to be a little more pronounced along with height and lyne arm orientation..

Cheers,
jonny

[Twisted Brick]

The smaller the diameter of your riser the higher the vapour speed .
Higher vapour speed means less separation of the fractions.
So small diameter riser needs to be run slower than a wide diameter riser

I agree with these, but I think there’s more at play here than just liberated fractions and vapor speed, namely what occurs in the boiler in the presence of a choke point. (Example: SP’s 1” riser).

On a pot still, a choke point creates the potential for an increase in boiler pressure and hence, boiler charge temps. This increase in charge temps can jumble and skew the linear ‘takeoff’ of volatiles, leading to smearing. The immediate remedy is to sharply slow production down. The permanent solution is to increase vapor path diameter, ideally through a condenser that itself does not present a choke point.

As always, still_stirrin explains it the best.

Complaints of smearing, visible condenser vapor (blowby) and forced slowed takeoff have been common from members who have contacted me about building/upgrading to a shotgun for their stills.

[Stout8174asheNC]

Riser? I’ve got a 3 gallon Vexar still with thumper. Right from Amazon. Check it out. Get back with me. Plz

[Stout8174asheNC]

My sweet feed corn yeast sugar mash. It’s fantastic. Sweet and tasty. Air lock goes crazy till about day 3 air lock basically stops. Mash turns super sour like vinegar. Why is that.???

[Sporacle]

Fermentation drops the pH and moves it into the acidic side, hence the vinegar taste