My first thumperruns

[Kareltje]

A week or so ago I finished building my one-hole-thumper and today I had a ferment ready to try it.

To be on the safe side I only wanted to fill both boiler and thumper with not more than 4 litres, both being 10 ltr in size.
First run with the boiler filled and the thumper empty, second run with both kettles filled and last run with the remaining 2 litres of wash in the boiler without the thumper. All run at full speed with 2,4 kW and the same watercooled Liebig.

The first run I stopped too soon. I always use boilingcents and listen to the rattling and when that stopped I was afraid all the fluid from the boiler was blown in the thumper. It wasn't, but I saw that only after taking the still apart.
The second run I ran to the end, although again the rattling stopped.
The third run I had only 2 litres left and for comparising I ran it with only the kettle.
I made graphs of both the %ABV of the samples and of the total distillate. I tried to stretch the time on the x-axis so that the graphs could be easily compared.

I learned a lot today, both of thumpers, condensers and energy.

Edit: I forgot to mention that the wash was about 11 %ABV.

[Pikey]

Nice one K

There's something wrong with your attachments - when you click on them, they come up in separate views but size is NOT increased.

You could put a thermometer in the "Head" of the column, or incorporate that manometer you drew on recent thread - either would warn of empty pot, if you cannot hear it boiling.

[Edit - are you heating the pot AND the thumper ? and what are you putting in the thumper - water or wash ?

[Kareltje]

Thanks.
The photo is small and I made the graphs smaller, thinking that might save space. Maybe that was unnecessary. I will read about attaching pictures.

Better?
There are two thermometer, normally used for meat, one between boiler and thumper, and one just before the condenser. Just to study the reaction time of the thumper. Thanks for your suggestion. One day I will build shadylane's manometer.

First attempt I had nothing in the thumper, second I had the cleanest wash in the boiler and a more dirty part in the thumper.
But I have seen all different combinations for all kind of purposes, like in the making of rum, but also in steamstripping and use like a ginbox.
Both are on my stove and I can heat both independently, so this gives me more possibilities than I can test!

I now have a fermenting wine of presscake of wallnut, that posed me some trouble in making it. I expect to really need the thumper in distilling that very heavy wash. The wash feels a bit like very heavy peanutbutter and will surely scorch when heated in the boiler!
Start with water in the boiler, than the first distillate in the boiler, second distillate etc. and every time a small portion of the wash in the thumper.

[Danespirit]

You have an interesting setup there, Kareltje.
A thumper always makes some noise, just before it comes online.
I remember my first run with such a thing...thought something was about to go terribly wrong.
Do you have passive heating on your thumper, like water in the stockpot beneath..?
You could cut the heat up time significantly, by insulating the two vessels.

[Kareltje]

That is the fun of this topic: the first run is always nerving and informative. The first few thumps were really thumps, but later it sounded more like a diesel: I use a showerhead as the head of my thumper. (That is a source of worry, for it could easily be blocked.)
I know that when running the 5th strip it will be less exciting, but this first run was indeed a thrill. More so because I used more power than ever before and I used my Liebig for the second time.

The vessels on the photo are in the nude, just posing. In pratice I cover them with a mantle of a 20-litre oilcan and the boiler is isolated with a alu-foil-plastic blanket used to cover carwindows. Saves me about half the energy: not less than EUR 0,50 per run!

I can heat the thumper, if I want.
There is a lot to experiment here!

[Danespirit]

Thank you for "letting her strip", so we can see what's inside.

A showerhead..?
I don't recall anyone else in here that mentioned such a setup.
As long as you don't distil with solids in the charge, that should be perfectly safe...but I understand your concern about a blockage.
You could widen the holes slightly and still have the same way of distributing the vapor.

[Pikey]

Kareltje comes up with some very interesting adaptions to push the bounds of convention sometimes. Always a guy to listen to and take note of

I think a shower head is great - used in "Blow" mode not "suck" mode, it should not be obstructed by boiler charge imho.

[Kareltje]

I got the idea seeing some piping in a thumper with small holes drilled in them to spread the flow of vapour. But I am thinking of a way to ensure safety. Preferably some relief valve or a sliding connection inside the thumper.
The sound is funny: like some dieselengine. As long as I hear that, it is still working.

[Shine0n]

The first time I heard the loud knocking I shut mine off thinking of an explosion was about to happen. Lol

There are so many ways to use a thumper, I'll fill mine just above or right at half and heat my boiler nice and fast to minimize filling of the thump.

You'll like this addition and once you learn it you'll learn to play more with flavoring and all the good things they offer.
Now you need to learn the thump keg waltz, lol
Shine0n

[Danespirit]

I got the idea seeing some piping in a thumper with small holes drilled in them to spread the flow of vapour. But I am thinking of a way to ensure safety. Preferably some relief valve or a sliding connection inside the thumper.
The sound is funny: like some dieselengine. As long as I hear that, it is still working.

A very simple, yet effective idea, is a tee installed in the horizontal pipe (Lyne arm)going to the thumper.
Plug the open branch of the tee with a cork stopper wrapped in a few wraps of PTFE tape.
Before any dangerous pressure can develop in the system, the cork simply pops out of that branch.
Simple, cheap, easy and reliable.

[Pikey]

How do you set the pressure the cork will pop out at ?

I'm not sure whether filling your kitchen with high abv ethanol fumes is more or less dangerous than filling it with natural gas or LPG fumes what do you think ?

[Danespirit]

It's not actual science and it's not a machined/tested pressure relief valve....so I can't mention any specific pressure.
However, the cork will most certainly pop out before the pipe or boiler ruptures...that's for sure (unless you hammer it in with some glue around).
I don't know where the distilling actually takes place...for me, it's my bathroom. Furthermore, the room can be ventilated through the upper window.
If one has a leak, it's going to leak..that's it and there is nothing one can do about it.
There is one thing one CAN do though...and that's to ensure the leak won't happen under high pressure.
I'd rather not have anything..a gas leak neither a leaking still, but let's face it...no matter how careful one is, the option for a leak is always there.

[Kareltje]

A cork in the described manner once saved me, indeed. And when one works with wash the vapour will have a strenght of about 60 %ABV and does not explode immediately. Distilling a low wine will hardly cause blocking! And when you hear the cork pop, you can shut of the fire, if you need to. Another sign will be the stopping of the sound of the thumper itself.

Reading in the thread of the relief valve I was thinking of making inside the thumper a construction like this:

Klep.jpg (4.87 KiB) Viewed 1741 times

In the downward 15 mm pipe I want to place a tee with a 12 mm side, then an elbow upward and then a connection 12-15. In this I can place a small steel ball. When the showerhead gets blocked, the ball will be pushed up and out and the construction will vent inside the thumper. The best of both constructions!
It should be made higher than the fluid in the thumper, so this ball can not be blocked in turn.

[Pikey]

Neat idea, do you think the ball would seat well enough to form a seal ?

I think if that ball bearing was steel (?) and 1/2" diameter, it would require a pressure of 0.9448 lb / sq inch (psi) to lift it.

That I think is somewhere around 25" water I think, so either you've fluked it beautifully, or calcuated - more likely that, I think ! - Nice one K

(Edit - That has to be the cheapest, completely safe way of doing the pressure relief valve. Destined to be HD standard recommend for thumper IMO )

Edit:

[Kareltje]

Thank you for your compliments!
No, I did not calculate it, but tried to reason how much 1 PSI is. Came to about 72 cm or indeed 28 inch watercolumn. I do not know the weight of a fitting steel ball, though, so I could not calculate further. The height of my thumper is about 36 cm, so a half filling will reach about 18 cm.

It is indeed doubtfull if the ball seals the valve exact, but that will hardly be a problem, when it vents into the thumper.
And off course the thumper should be open to the atmosphere via the condenser, so the contents are not supposed to cause any blockage.

By the way: I always use a thermometer, which is fitted inside a small pipe with a cork, so I always have a safety valve.


It seems my wallnutpresscakewine is almost finished: sg = 1,000 and I started with 2,5 kg sugar in 15 litres ferment.
I have about 5 cm liquid and 18 cm sediment! So the thumper will have to go to work!

[Pikey]

Hi K,

The weight of a ball bearing in steel can be found here - but in Imperial units. I used teh 1/2" one which is 12.5mm - unfortunately I think I got it wrong by a factor of 10 !

http://bearingballstore.com/index.php?m ... =page&id=6

The effective surface area I took as a circle of diameter 1/2" and came to 0.196428571" sq. I then simply ddivided the weight of the BB by the cross section area to see how much pressure would be needed to support a 1" plate of the same weight per the same area.

Unfortunately, in my original typing I missed the first zero off the weight and thus had it ten times the weight. So my assessment now is that you are looking at a pressure of only something like 2.5" water or 60 mm ! which is of no use for the purpose.

Would somebody please check my logic and arithmetic - as this is quite important for the design and needs to be done correctly !

Sincere apologies K

[Kareltje]

Hey Pikey,

Well, it is hard to order 1 bearing ball of a specific size, so I was planning to just weigh a suitable size if time came.
Funny chart though: I never thought of bearing balls of almost 2 kg a piece!

But I go back to the main concern: what if my showerhead inside the thumper gets blocked? Then I need a safety valve to prevent explosion or disruption of the kettle.
When pressure really gets too high, the thermometre and its cork will be blown out and the low wines will vent into the air. To prevent that a safety valve can be build into the input pipe to the thumper, like I drawed.
The pressure that keeps the ball on its seat is not really important, although it might be interesting.

Suppose the showerhead is blocked.
Then the ball is lifted from its seat and the pressure is released in the thumper. No problem: the stilling can go on.
Or the ball is too heavy to be lifted. In that case (disregarding the cork and its thermometer!) the boiler will burst or explode. But I can not imagine that. For that to happen, the ball has to be almost immovable/screwed/welded/soldered.

It is not concievable for me that a ball in a 15 mm OD (= 13 mm ID) pipe can be heavy enough to block the boiler completely until explosion! So in my mind the ball will be lifted and overpressure will be vented inside the thumper.

[Pikey]

Hi Kareltje, What I'm saying is that I think the ball is way too light. Hopefully someone else will do the calculation as well to confirm. If you went to a bigger diameter pipe, it may be a very satisfactory solution, but as is, I think it would just bypass your thumper at all times.

Sorry mate, I thought it was so elegant.

[Kareltje]

Hi Kareltje, What I'm saying is that I think the ball is way too light. Hopefully someone else will do the calculation as well to confirm. If you went to a bigger diameter pipe, it may be a very satisfactory solution, but as is, I think it would just bypass your thumper at all times.

Sorry mate, I thought it was so elegant.

Good point! Thank you.
Before I make this thing, I will calculate a bit. Maybe more balls or a wider pipe, like you suggest.
The venting inside the thumper is elegant and safe, as long as the outlet of the thumper is not blocked.

I did six runs with a heavy slurry and it really was informative.
The showerhead is easily disturbed.
I did some runs with only water in the primary boiler and the thermometer reached 105 dgr C! And when I blowed the inletpipe to make sure it was free, it took some effort. Nerving runs!
boiler and thumper loaded with about 10 %ABV wash half diluted: started at 56 %ABV
boiler loaded with water, thumper with half diluted 10 %ABV wash: started at 37 %ABV
boiler loaded with water, thumper with 10 %ABV wash: started at 57 %ABV

There is some sweating on the lid of the thumper, because the soldering on the large, aluminium lid did not go very well. Used some grit to bind it.

[ShineonCrazyDiamond]

Maybe more balls or a wider pipe, like you suggest.

Why didn't you listen to the misses when she made the same recommendation?

[Danespirit]

There is some sweating on the lid of the thumper, because the soldering on the large, aluminium lid did not go very well. Used some grit to bind it.

Aluminum, ain't recommended for distilling equipment, as it will oxidize and degrade.
A lid out of stainless steel or copper is preferable.
If you have some trouble sourcing it, you can make a quick n' dirty fix with a PTFE sheet.

[Kareltje]

Well, the lid is, no was, the bottom of a good ss pan and is apparently at least 3 layers: thin layers of ss at the outside and a thick layer of silvery, soft, smearing metal inside. The aluminium will never touch the alcohol, only the drops that leak out.

I lack experience in soldering, so I am not sure what went wrong, but the solder seemed to become fluid and then solidified again. Did not stick well on the ss and not even on the copper, so I assumed the aluminium took away the heat very soon.
But the leak is very small, not more than a bit of sweat, and can easily be absorbed by some meal.

As I will not run high % wash in the thumper, this will not be a great problem. And else we will solve it, if need be.

[Danespirit]

I'd figured where the bolts go though would be the culprit.
You could wrap them in a thin layer of PTFE tape, but make sure it seals up the hole so no vapors go inside.
The assumption you had is right...Aluminum is an excellent heat conductor (almost as good as Copper).
So it "wicked" the heat away from your soldering spot.
That's also the reason why the solder didn't stick.
For stainless steel, I recommend silver solder. The only problem is...the more silver contend, the more heat is required and a normal blow torch may not be sufficient.
One CAN solder with plumber solder on stainless and it will provide a joint that is strong enough for our purposes, provided there ain't a lot of pulling force on that joint (it ain't correct craftsmanship, though).

meal..? As you are from the Netherlands, friend, you probably mistranslated the word from "Meel" . Think "flour" was the right term...?

You should have a look around and find a plate of stainless or Copper for that lid, that would eliminate any possible safety concern.

[Kareltje]

I will watch the holes for the bolts to check for corrosion, but did not (yet) see any sign of leaks there.

I used a silver solder at first, and when it did not stick I tried a solder with more lead, supposing it needs less heat. (And it is on the outside, so will not contaminate the distillate.) Later I thought that maybe I should have fired up the torch.

When the problem will get worse, I might try again or ask help from someone who is experienced.
The problem is not the material, but the defects in the passing through the plate. Even pressing parts together with screws is not failsafe. But it is more like sweating than like leaking.

Yes, meal seemed a perfect English word. And it is, but for something completely else.
You know Dutch?

Funny thing: when I typed it in on googles searching bar, it was completed as: meal på engelska. Connected with Swedish sites.
Jeg ved: Danmark er ikke Sverige. But it was surprisingly close.

[Danespirit]

I will watch the holes for the bolts to check for corrosion, but did not (yet) see any sign of leaks there.

I used a silver solder at first, and when it did not stick I tried a solder with more lead, supposing it needs less heat. (And it is on the outside, so will not contaminate the distillate.) Later I thought that maybe I should have fired up the torch.

When the problem will get worse, I might try again or ask help from someone who is experienced.
The problem is not the material, but the defects in the passing through the plate. Even pressing parts together with screws is not failsafe. But it is more like sweating than like leaking.

Yes, meal seemed a perfect English word. And it is, but for something completely else.
You know Dutch?

Funny thing: when I typed it in on googles searching bar, it was completed as: meal på engelska. Connected with Swedish sites.
Jeg ved: Danmark er ikke Sverige. But it was surprisingly close.

There we have two problems already.
1: As you used silver solder (probably just heated with a blowtorch?), you didn't get sufficient heat into the materials...hence the missing connection between solder and material.

You can do something about this issue, by using a torch with more power, such as Acetylene and Oxygen.
You might even get away with preheating of the whole workpiece before you apply solder....remember to clean everything thoroughly..! A coal fire in a grill may be enough, I've used this trick a few times.

2: Regardless of the solder doesn't touch anything in the product path, lead solder is a bad idea. Normal plumbers solder is a way better alternative.
It doesn't take as much heat to melt it as silver solder requires.

No, I don't speak Dutch, but I understand it when people speak slowly. Funny, some of the words spoken in your language are the same in our dialect we call Sønderjysk (Southern Jutland).
As an example the word meel in Dutch...in Danish it's called mel ...almost the same.
Ha, ha...no indeed..Denmark ain't Sweden, but you were close. With Finish (Suomi) as an exception, the Nordic languages are closely related. So more or less we all understand each other.

[Kareltje]

Thank you for the advice!
I already had soldered some pieces and that went well. And I read the advice for complicated pieces to work from higher melting solder to lower melting kinds, which seemed a sound advice.
I used the lower melting solder on top, but indeed had only a blow torch.
When I need to repair it, I will remember your advice.
I thought of putting it on the burner of my stove and than soldering from the top.

I few years ago I went on holiday to Denmark and tried to learn a bit Danish. There were quite some words that looked alike, but the meaning had shifted. Gammel is old in Danish and almost falling apart in Dutch. Stor is big, stoer is tough (as in tough guy).