Stovetop Thumper

[Usge]

That's basically what I did this last run LW save for very slow heatup of boiler. Thing is..I'm using underpowered stovetop gas (old) ...with a steel grate over that to spread the heat over 16 inches. Even full out, it's not all that much heat...nothing like using one of those propane rigs. Using 1/4 gal gal water in 2 gal barrel..left the angle cut outlet tube only partially covered so the thump barrel did fill itself this run. I do have a therm on the head of the potstill, but it's easy enough to tell when the thumper is coming on line...because the lynearm gets hot. Once it got hot...I could hear it "dripping" (filling) the barrel. Prior to that, I could here the thumper "huffing"/knocking as vapor/pressure made its way through the partially covered outlet. I just made sure the liebig was full up..so nothing leaked out. No distillate started to drip out till the thumper finally filled and got quiet(er). Beyond that, it did just as you said this last run...the head temp reading on my therm on the pot...rose throughout the run...while the abv of the distillate coming out of the thumper stayed at a steady 82-83% for most of the run...falling fast towards the end.

I also ran it just as you said..after that. It was a broken stream/dribble the whole way. But, next time, I'll try bringing the boiler up slower. It's unfortunate, the one thing I really dug about this was running wash because it would come off right at barrel proof, and very smooth. But, it appears I'd need about a 50 gal pot to get anything out of it that way....just not enough alc in the pot to start with. Maybe running it slower on start up with wash will make a difference? We'll see!! Last time I think I got about 400ml off a 5 gal 8% wash. The rest was either heads or tails.

I'm also dealing with a stuck mash right now. Just over did it . I mashed 8lbs of indianhead cornmeal with 2lbs malt — messy but it worked better than I expected. Then put 8lbs of sugar in it in 6 gals of water . I tossed Lalvin EC-1118 in it 2 days ago..and all it did was just slight, foam on the top..but no co2 or bubbling in the airlock. So, I added more yeast...still same thing. You can see the yeast making bits of foam bubbles on the surface, but nothing beyond that. No gas coming out. So, I guess I'm gonna have to split this one up and water it to even get it going..or just let the yeast chisel away at the top for a month or two till it finishes. No worrys though, I got a another sourmash going on the side (soured cornmeal cooked in with boiling water, malted, then sugared). Was gonna run my apple cider, but it turned out unexpectedly good, and decided to just put some oak on it and keep it as is. Should have something to run this weekend.

[flip]

Hi Usage,

i like your thumper,
But i like to see through a thumper, because in mine the fluid rises towards the end.

and the size does count, to be the same size of that what you wish to distill.

think i read it somewhere in parent site.

[LWTCS]

If your heat source can handle it, try crankin it up as soon as you can confirm your last bit of intolerable heads

And do like Dunder always recommends and start with a lower abv to git ya that much closer to your prefered barrel strenth.

I think you've got it. You just need more repititions.

[Usge]

Thanks LW. Will do.

[Usge]

....
I also ran it just as you said..after that. It was a broken stream/dribble the whole way. But, next time, I'll try bringing the boiler up slower. It's unfortunate, the one thing I really dug about this was running wash because it would come off right at barrel proof, and very smooth. But, it appears I'd need about a 50 gal pot to get anything out of it that way....just not enough alc in the pot to start with. Maybe running it slower on start up with wash will make a difference? We'll see!! Last time I think I got about 400ml off a 5 gal 8% wash. The rest was either heads or tails.

So, here's the stats on the last run. Used 5 gals of corn thin-mash (mashed Indian head corn meal/barley + sugar). I put 1/4 gal water in the thumper so it would fill itself again. I brought it up slow this time..taking almost 2 hours before it started dripping. I had the heat on "med" on one eye on gas stove with grate covering 2 eyes. Distillate came out at dribble...never streamed.

12:10pm Heat on Med (front burner only)

2:32 200ml fores
1 - 2:51 175ml 75-74% (head temp on pot) 198F
2 - 3:00 175ml 74% 200F
3 - 3:10 185ml 73% 200F
4 - 3:20 150ml 72% 200F
5 - 3:30 175ml 70% 201F
6 - 3:41 175ml 69% 201F
7 - 4:00 290ml 67% 202F
8 - 4:20 300ml 64% 204F
9 - 4:40 300ml 60% 206F
10- 5:00 280ml 55% 207F
11- 5:30 470ml 45% 209F (heat up full/high)
12- 5:48 470ml 34% 210F (shut down)

Total run time (including warm up) to shut down. 5 hrs 38mins.

If you had to guess by abv, etc., where heads/hearts/tails would be...what would you guess?
The entire run was heads smeared directly into tails...there were no hearts to collect. I saved everything to try again. But, it's a little disappointing. Here's the totals:

Total collected (including fores) = 3345ml (3.34L)
Fores = 200ml
Obvious Heads = 1040ml
Hearts = 0
Obvious tails = 2105ml

Average flow rate per min = 16ml per min (not counting the last 2 pints of tails flushed out on high heat)

The data tends to point to it running too fast/too much heat. So, the obvious question is...does anybody here think 16ml per min too fast for a potstill with a thumper?? Or, I should say...is 16ml per min driving enough heat to smear heads and tails through an entire run on a 5gal pot with thumper? That's a little hard to believe, but I put it out there cause that's what the data "seems" be saying.

2ndly, mostly..it looks like a typical pot still run (without a thumper). The temp rose fairly steadily after sticking for only the first few jars, and the proof dropped linearly. Last thing puzzling me is...when I put more alc in the pot (ie., low-wines or feints), it works like it should (head temp rises, put proof locks in and stays there for most of run) and leaves a few clean jars in the middle. When I try to single run wash...it falls apart. I've tried this same run using wash in the thumper instead of water...same thing. This time, the thumper filled itself so I know it had low wines in it. Same thing.

I'm starting to think that 5 gals of wash is simply not enough alc for it to work properly. The bearing of the thumper seems to make no difference (full or empty/ water/wash/or lowwines) when I'm single running wash/mash. It doesn't appear to respond properly until there is a certain threshold of alc/abv in the pot to start with. That's regardless of what's in the thumper or heating it up slow or fast. But it does seem to work properly/fine when running 30-40% off the pot.

I have to say as well...this pretty much mirrors my experience trying to single run wash/mash without using a thumper as well. It pretty much goes from heads...straight to tails. Even if I drip it off over hours...with the heat so low ...vapor barely makes it over the lynearm. It just never seems to work properly unless I load up the pot with a 30-40% charge. I'm guessing as well, could have been something with the wash/mash as well. It was pretty stressed/slow to ferment. Had 8lbs of cornmeal, 2 lbs of barley mashed, and 8 lbs of sugar in 6 gals of water. Maybe it just produced nothing but nasties..etc.? That could be part of it too. But, the data seems to show 2 things...that the thumper is not responding properly when wash/mash is used in the pot...regardless of whats in the thumper or whether it fills itself or not. And 2, that it seems to be smearing the run indicative of too much heat...even at 16ml per min flow rate.

I'm open for ideas/suggestions/analysis. And THANKS in advance....

Trying to get this nailed down and get my sanity back - Usge.

[Barney Fife]

I'm thinking you want to insulate everything from the pot to the thumper, and insulate it well; while the thumper is self filling and that is a good sign, the results show it isn't working well, if at all at all. With the long run between boiler and thumper, you're likely getting too mush cooling and the thumper isn't getting enough heat to do the second distillation. Insulation is cheap, so try this first.

[Usge]

Thats an interesting observation Barney. And it makes sense on the one hand...ie., that the thumper works with higher abv..but lower abv wash isn't reaching high enough temp for it to work properly — although it sounds like the thumper is boiling vigorously. The catch 22 other side of that is...it's not reaching high enough temp for the thumper to work properly...but apparently is reaching high enough temp using 1/2 of one burner to smear tails through the run. If it needs more heat, I've got plenty more burner to drive it harder with — plus can add the back burner as well. But, my guess is, that's only going to make the smearing of tails worse? I'm not sure I can use insulation on the copper pot on a gas stove...but I can surely insulate the lynearm and wrap the thump barrel. What would you suggest as insulating material?

For comparison...here's data from previous feints run (watered to 40%)
250ml fores
1 - 3:59 pint 84% 183F
2 - 4:25 pint 83% 184F
3 - 4:44 pint 83% 185F
4 - 5:03 pint 83% 186F
5 - 5:21 pint 83% 188F
6 - 5:41 pint 83% 190F
7 - 6:00 pint 83% 190F
8 - 6:20 pint 83% 191F
9 - 6:42 pint 83% 193F
10-7:03 pint 82% 195F
11-7:24 pint 82% 197F
12-7:43 pint 81% 199F
13-8:02 pint 80% 201F
14-8:16 pint 78% 204F
15-8:29 pint 75% 206F
16-8:40 pint 72% 208F
Flushed rest out from there down to 40%.

[LWTCS]

Hmm,

I'm wondering now if the thumper is just too small,,,(for a wash).

Maybe just not enough headspace to get adaquate separation as vapor starts to accumulate within the keg?
Perhaps the space is so small, that the boil(or maybe air pressure) disrupts any kind of fractioning?

Wonder if you had a taller riser out of your thumper to give yourself a bit more room for fractioning? Or a taller/bigger thumper

[Usge]

Thats an interesting thought as well LW. Thumper is 2 gals. Pot is 5. It's close to half the size of the boiler. On the feints run...it was about half full when finished. On the wash run, it was less than half full (about 1/3). The barrel isn't getting full by any means. And as before, separation seems to be working just fine when I run low-wines/feints. Just not with wash. Hmmm.

[goose eye]

rockwool

mite wanna try a little fire under your doublein keg that you can walk

so im tole

[Barney Fife]

I'm not suggesting you run your boiler harder, but that the thumper itself is too cool. Since you're not going to build a fire under it, you can insulate everything from the boiler to the keg/thumper, including the keg/thumper.

Also have to wonder if having the feed and outlet at the keg built into each other as you did causes something to happen that was unforseen?

[Usge]

Thanks guys....well...don't know if the wifey let me build a walkin fire in the kitchen goose . But, I take that your sayin same thing Barney is...that the keg is too cool? And Barney, I'm wondering about the inline design as well — ie if it's restricting something or not? Doesn't seem to be. And it has the same volume, output (1/2 inch). But, can't discount that either.

I'll get something from homedepot to insulate the lynearm and thumper with. Also, wondering...if maybe putting high proof feints in the thumper might be a way to test this theory out (given the feints might raise the abv in thumper juice enough to kick it off at lower temp — ie., easier? Anyway, at least it works with low-wines. That's a start I guess.

[rad14701]

Usge, when I first read your post about the all heads and tails run my first thought was that your thumper might be too big and/or holding too much liquid... With a 5 gallon wash you will only have so much alcohol and if it gets into the thumper you'd need tails to push it put... And if your 2 gallon thumper already has heads and hearts in it you'll just end up with a smeared run... Can you get into your thumper to add something that would offset some of the volume to prove this theory out...???

[Usge]

I've got some oak cubes that will fit in there...maybe fill up some of the volume?

[goose eye]

put it in a pot of water if you aint ever cooked a wood barel before. get temp up so
it aint startin from a dead stop. make sure you rise it a wee bit slower than the kettle so you
aint getin negitive vaper flow. once it gets where you want it turn the wick back an let the kettle
take over or keep walkin it

so im tole

[Usge]

Ah...I get it now goose (ie., walkin fire..as in walkin it along...as well as walkin the log back and forth hotter/colder). Not sure how I can logistically run a heat source in the window sill. But, I can pre-heat the barrel in hot water for sure. I could also put it in a pot and pour hot water in it — just wouldn't have any way to keep it hot after that point.

I'm starting to understand OD's design of having the lynearm wrap/coil around a copper thumper...so that by the time the pot is read to give it up..the thumper is pre-heated.

Just came down with the crud (throat, nose, etc.) Bleh. So, I foresee a couple days off in my future. Got some wash working for the weekend. Gonna try some experiments then. I really appreciate all the help/suggestions. At least I have a direction to go in for stuff to try. Just have to figure it out.

[LWTCS]

I'm starting to understand OD's design of having the lynearm wrap/coil around a copper thumper...so that by the time the pot is read to give it up..the thumper is pre-heated.

And with mine (s) I get really good thermal transfer alah the design. Never run anything else but mine.

[Usge]

LW, you and OD have definitely got the skills in the build/design dept. Since I bought mine originally..I spent the first couple years just running them only to discover the various limitations, etc. I've just gotten into building things so I could mod up what I have and I've really enjoyed it. But, you guys are on another planet in that regard. I've managed to build a couple liebigs that don't leak, a parrot, and various plumbing needed to rewire my CM hybrid Colonel's Ga Ridge head. This thumper was my lastest project...I made the thump head using OD's drawing. Prior to doing any of this..I never soldered a thing in my life. Just had to jump in and do it. It's almost as great a satisfaction building things as it is running them. But, problems, issues..etc., are always frustrating (as is the case with this).

I just got back from the kitchen...and I think its possible that I can reposition everything on the stove top, etc..in such a way that would make it possible to cut the lynearm length in half. Along with some insulation..perhaps that might improve things some as well in getting heat to the thump keg. I think I have enough copper/parts to build it without hacking up the one I have (incase it doesn't work out). Again, as always...thanks for the help/direction. I'll keep plugging at it.

[olddog]

I never soldered a thing in my life.

Before getting into stilling, I had never soldered anything other than a circuit board, soldering aint hard you just gotto do it.


OD

[Usge]

I know OD that you also work with minimal space, tools, etc. That just makes what you do all the MORE amazing and inspiring for the rest of us blobbers out here

[olddog]

I think that Larry is filling spaces at his More On The Floor School of Soldering for the next semester.


OD

[LWTCS]

I think that Larry is filling spaces at his More On The Floor School of Soldering for the next semester.


OD

Haha. Yet another saying to be printed on a t-shirt. Crime of it is,,,,,,,I been soldering (on an off) for 20 years

But I'm not really that bad

[Usge]

Larry, your builds are great. The capability to be able to envision it..see it in your head...understand it...and just work it out to make it work...regardless of how much solder is left on the floor at the end is amazing. Most of the stuff you guys get into is simply over my head — dephlemator where I come from is something you use when you are sick..have phlem. Speaking of which...I feel like my head is about to pop! Home sick today...but took the opportunity to mod my lynearm. I figured other than getting insulation for the arm and barrel (which I can't do till I can get out of the house), the most direct/easiest mod I could make would be to simply move the barrel as close as possible to the left side of the window and cut down the lynearm. I took nearly 14 inches off it.

After

ModLyneArm.jpg (8.26 KiB) Viewed 1986 times

Before

If that doesn't do it, the next would be to shorten the thumper head by about half, and then raise the barrel up to compensate for the vertical clearance I need for the liebig. That would be a bit more complicated (Pain) to have to do..so I'm hoping this will get it going.

[Usge]

Well...it appears shortening the lynearm by almost half and insulation does not change this strange behavior. As well...it doesn't appear to be a heating up problem.
Data from latest run: 5gal apple cider (9%) and 1/4 gal of cider in the thumper

11:45 heat on
2:46 160ml of fores 198F (dripping off slow)
3:19 200ml 80%-79% 200F (measured from parrot)
3:35 200ml 79% 200F
3:52 200ml 78% 201F
4:11 200ml 77% 202F
4:30 200ml 75% 203F
4:49 190ml 73% 204F
5:10 200ml 71% 205F
5:34 200ml 67.5% 206F
5:58 200ml 64% 207F
6:09 200ml 57% 208F
6:26 450ml 42% 209F
6:38 470ml 30% 210F (heat off, emptied parrot into jar)

So, again...with mash/wash in the pot...the thumper doesn't seem to respond—the abv falls constantly as the vapor temp rises leaving heads and tails uncompressed. With higher abv in the pot to start...it does respond properly and holds abv steady for most of the run. So, as an experiment...I also ran wash using the hybrid CM head under reflux and looked back through my notes for runs on low-wines. It does exactly the same thing. With higher abv pot charge...it will hold abv and compress heads and tails. With wash/mash in the pot...it starts out a bit higher in abv..then falls every jar as the temp rises...just like a straight up pot still run — leaving heads/tails uncompressed and very little middle. I'm repeating the same results here over and over using different equipment. I don't know what to say at this point. Are we sure that this not normal behavior?..given I've repeated the same results on different equipment? Or are my expectations off? Is anybody else running straight up thumper on a 5 gal pot seeing results like this or can confirm this finding? I think I'm chasing a ghost here.

[LWTCS]

Usge, when I first read your post about the all heads and tails run my first thought was that your thumper might be too big and/or holding too much liquid... With a 5 gallon wash you will only have so much alcohol and if it gets into the thumper you'd need tails to push it put... And if your 2 gallon thumper already has heads and hearts in it you'll just end up with a smeared run... Can you get into your thumper to add something that would offset some of the volume to prove this theory out...???

Opposite side of the same observation

Been thankin.
So it is good that the rig does well with a striped charge. I'm thanking the keg is too squatty,,,,and wondering about the speed of vapor entry into the lil keg.

I'm wondering how well a wash would behave (in this instance) with a thumper vessel of the same volume,,,,but perhaps twice as tall?
Maybe give your vapor more time to get into pecking order?

Know what I mean?

Speculation at your expense

[Usge]

Thanks LW. Well...I chose the wooden barrel cause it was most commonly used in past. And 1/2 size of boiler (mines slightly under 1/2) is a common recommended size. I've seen people run mason jars....and I've seen people run barrels same size as boiler....I've seen long lynearms and short ones...nary one of them do I recall mentioning having a problem or difference with single runs. Most people used one so they could single run wash/mash. And as far as I've ever seen...they all talked about them compressing heads/tails..holding steady abv...and making for clean cuts. Given all that, I can't believe I just happen to pick just the right combinations of things to make it all "not" work
hahahaha.

As far as boil/vapor speed...it boils the keg good....can hear it. The thumper head shows that on a wash..it only fills the keg about 1/3 full. So, there's plenty room in there (as to your and Rads divergent points). On the low-wines run...it does fill the keg to a higher level (bout half or more). I can always start with more wash/water in the thumper ..which would in effect reduce the overall air volume inside the barrel..although it may increase warm up time...which is fine. Last time...thumper started chugging along for about 30mins before it finally started dripping. Head temp on the pot held still the whole time. So, I think its taking care of itself in regards to warmup..just have to give it time.

Got my vacation coming up soon:) I can try a few more things when I get back. But, at some point...I'm just going to punt the whole thing and look towards building something from scratch. Something other than a potstill (which I have coming out my ears), that has tuneable reflux...up to near neutral...but low enough to make a nice, compressed heads/tails...clean dilenated cuts run on corn mash. Still a potstill guy at heart...but looking for cleaner cuts. Open for suggestions.

[LWTCS]

As far as boil/vapor speed...it boils the keg good....can hear it.

Gotta wonder if the smallish stuff just doesn't scale down the same.

I was wondering if the smaller lyne arm was allowing vapor speed to build to the point where it was causing an additional amount of turbulance when entering the keg? Which then would set things to smearing?

I'm pretty excited for Myles new build. Beyond that,,,,,,,,,flute.

[Usge]

Iv'e been catching up reading on the "flute" (both OD and KS). Fun stuff. But, maybe I should start out with something a little simpler through

[Usge]

I was wondering if the smaller lyne arm was allowing vapor speed to build to the point where it was causing an additional amount of turbulance when entering the keg? Which then would set things to smearing? .

Did the same thing with the longer lynearm.

[Barney Fife]

Size of lyne arm, not length, is what LW's speaking of. He might be onto your problem there. Think of a garden hose, and how you place your thumb over the end to get it to shoot a finer, faster stream. A venturi. Your tiny lyne arm might be speeding the vapor to where it's just going too fast for any separation to happen.

It's a thought. I've never run anything smaller than a 2" column or lyne arm, myself. Any chance you could up-size it up to 1" or 1-1/4"?