3" or 4" column?

[Dannbo]

New to the site recently after hanging out reading for a while. I don't see too much on a 4" Boka build. As stated in my introduction, I'm constructing a Keg boiler with a Boka column. My intention is to be able to switch out for use as a pot still as well. I have a fairly good handle on the design thanks to research here and elsewhere, but I ran into a bit of a snag. When I fabricated my double wound helix coil I made it slightly big for my intended 3" column build. I figured I would just use a 4" instead as I have access to any sizes of stainless. This brings up issues I was not counting on.

I have only 30 amps available in my shop to run the still. Do you think a 4" column is too big to run on a 53l keg with a 5500w element? Or would it be easier to just make a new coil the right size for a 3"?

A little additional info. So far I have a 53 liter stainless keg, a bunch of stainless tri clamp fittings, a stainless valve that I may have to change out for larger size, home made copper Liebig condenser, home made copper double coil condenser, and access to any size stainless tube. Also I have bought parts for the control box. Still have a ways to go, however a good start. I have good metal fabrication skills and lots of good items to trade my neighbor in exchange for his tig welding skills.

[30xs]

I’ll try to help what I can.

The 5500 watt element will draw about 23 amps at full throttle. Your 30 amp service should be up for the job.

I’m not too familiar with a Boka, but I think 3” is the norm. 4” is usually plated columns. Packing has the potential to collapse under its own weight in the larger column. I may be wrong, but I would say the 3” is the better option.

[Saltbush Bill]

3inch is about as big as most have tried to go with a boka.
Weight and hight issues along with copper packing collapsing under its own wieght are just a few of the reasons I've heard for not going bigger.
2 inch boks are notoriously slow.........3's are much much faster. I run a 3 and wouldnt change what I have.

[pope]

What product do you want to make? Only vodka or do you want to do other spirits? If you have the skills I would consider whatever is most convenient for you to mod for more flexibility down the road. You can make a 4" boka but you'll want sturdy support for your packing and you'll want to go with something more like rasching rings, spp, lava rock, etc. Something that won't collapse under the heavy liquid weight - mesh will compress.

[shadylane]

I have only 30 amps available in my shop to run the still. Do you think a 4" column is too big to run on a 53l keg with a 5500w element? Or would it be easier to just make a new coil the right size for a 3"?

I have a 4" CM packed column on a 70L boiler with two elements.
Around 6500w is the max It can run a sugar wash before the boiler starts foaming up.
Given a choice between 3" and 4" I'd always pick the 4 incher
The column uses SS mesh and works very good

[NZChris]

4" is better that 3" for the same reasons 3" is better than 2". If you are worried about weight, hang it from a block and tackle.

You can use more than one packing type and can use sturdier packing at the bottom than you use at the top.

[bluefish_dist]

Go 4”. Also you don’t have to use plates. I am now running a short section of marbles instead of plates as I sold off my 4” plated sections. By varying the height you can get the equivalent of a different number of plates.

[cayars]

Are you dead set on a boka build?
It's going to run slower than other still types. A Boka isn't the best overall still type IMHO, but it might depend on the spirits you wish to produce.
For a keg with a Boka I'd agree with NZChris and bluefish_dist and say a 4" column will benefit you as you will have a lot more vapor in the column to work with.

But I'd question the choice of still to build and ask if you have explored other types of reflux stills such as CM or VM? More importantly I'd ask what type of spirits do you intent to make? And also if you have other stills to use?

[bluefish_dist]

If I was going to build a still from scratch, I would do a ccvm or vm. 4” column and then neck it down to 3” for the condenser And T. 1/2 CSST fits nicely in a 3”. Then neck down to a 2” shotgun condenser or just use a 3-2” T. Way easier to build and it will be a solid runner. No cutting or welding required, just assemble parts. If at some point you wanted a vm, then just add a valve on the takeoff and don’t move the condenser down.

[cayars]

That was my thinking bluefish_dist as well., but I wanted to hear back his intentions and types of spirits he wanted to produce before commenting.

[The Booze Pipe]

In America bigger is better. Which ever you build, make it modular so you aren't locked into one setup. I just put together a 3" CCVM using tri-clamp connections. The different configurations are endless

[Dannbo]

Wow, lots to take in, thanks to everyone. As a novice It takes a bit of time to research your suggestions. My choice for the Boka build came about just through a lot of reading. I am not stuck to any one design really. I suppose the most of the parts I have collected so far would work for any design. Fabrication is not really an issue as I am comfortable working with these materials. I would like to tri clamp everything.
My intention is to initially make clear pure spirits in one run hopefully with an option of pot distilling as well.

[Expat]

Wow, lots to take in, thanks to everyone. As a novice It takes a bit of time to research your suggestions. My choice for the Boka build came about just through a lot of reading. I am not stuck to any one design really. I suppose the most of the parts I have collected so far would work for any design. Fabrication is not really an issue as I am comfortable working with these materials. I would like to tri clamp everything.
My intention is to initially make clear pure spirits in one run hopefully with an option of pot distilling as well.

Some solid advice you've received here; sounds like you have a good plan forming Modular is definitely best, switching modules for different effect is fun!

Bigger, faster, better... always?

Bigger means larger equipment to store, bigger means more energy to run and more cooling to manage it. Bigger means larger ferments and therein larger bets on recipes. There is no doubt that scaling will let you make MORE, but how much do you really do you actually need/want to make? Do you have the space or need to go that direction?

My $0.02, with a 3" build, I could in a matter of a few weeks, produce more than I could hope to drink (or share with my closest friends) for literally years. Which is admittedly fun when you're building stock for aging, but there is a limit. So that is a long way of saying, Smaller can be better depending on your needs, and I would advocate for a 3" setup as a good balance of speed and overall production capacity.

[Dannbo]

Wow, lots to take in, thanks to everyone. As a novice It takes a bit of time to research your suggestions. My choice for the Boka build came about just through a lot of reading. I am not stuck to any one design really. I suppose the most of the parts I have collected so far would work for any design. Fabrication is not really an issue as I am comfortable working with these materials. I would like to tri clamp everything.
My intention is to initially make clear pure spirits in one run hopefully with an option of pot distilling as well.

Some solid advice you've received here; sounds like you have a good plan forming Modular is definitely best, switching modules for different effect is fun!

Bigger, faster, better... always?

Bigger means larger equipment to store, bigger means more energy to run and more cooling to manage it. Bigger means larger ferments and therein larger bets on recipes. There is no doubt that scaling will let you make MORE, but how much do you really do you actually need/want to make? Do you have the space or need to go that direction?

My $0.02, with a 3" build, I could in a matter of a few weeks, produce more than I could hope to drink (or share with my closest friends) for literally years. Which is admittedly fun when you're building stock for aging, but there is a limit. So that is a long way of saying, Smaller can be better depending on your needs, and I would advocate for a 3" setup as a good balance of speed and overall production capacity.

Thanks for the info. Given all the things you mentioned and my limited height of 8' in my garage, I will stick to the original 3" design. I cut my double wound coil apart and removed the oversized windings. I will fab up a splice and silfos everything back together. I think I still end up with about a 10" double coil.
I think I will also keep with the Boka design. I will do some more reading on the ccvm as others have mentioned before my final decision. I need to research what benefits I would incur. Not sure why it would be an advantage yet. Are they faster? Can I still get the highest % with a ccvm? lots of reading to do. Again, thanks for the help everyone!

[The Baker]

I have some two inch copper pipe and some four inch, no three inch.

If I were thinking about a column that would influence my decision.

Geoff

[Fivey]

I think I will also keep with the Boka design. I will do some more reading on the ccvm as others have mentioned before my final decision. I need to research what benefits I would incur. Not sure why it would be an advantage yet. Are they faster? Can I still get the highest % with a ccvm? lots of reading to do. Again, thanks for the help everyone!

Yes, Boka stills are notoriously slow. Any VM and specfically CCVMs are significantly faster. [EDIT: I have struck out the previous statement as incorrect. Boka stills do have a reputation for being slow, but the takeoff rate on any reflux column relates to the reflux ratio and at the same reflux ratio you are getting the same takeoff rate - any perceived difference in takeoff must relate to other factors, and all other things being equal, a Boka and CCVM with have the same takeoff at the same reflux ratio] You can do as well with a CCVM in terms of high ABV neutral as you can with a Boka.

Here is the DAD300 CCVM design thread: viewtopic.php?f=1&t=41579&hilit=controlled

[Yummyrum]

I am not so sure why we keep seeing an increase of comments regarding VM or CCVM being faster than Boka ( LM)

I’d like to know where this idea come from ?

Reflux ratio , packing type , hieght of column ... all these things effect purity . How does still head type. alter any of that ?

[jedneck]

I am not so sure why we keep seeing an increase of comments regarding VM or CCVM being faster than Boka ( LM)

I’d like to know where this idea come from ?

Reflux ratio , packing type , hieght of column ... all these things effect purity . How does still head type. alter any of that ?

Agree with yummy.
I run a lm/vm on top of plates. Also have a cm head. All of them will output at same rate. Mostly i bleed fore n heads through lm then hearts on vm.
Its not still head that controls speed it operator, in my opinion

[Fivey]

I am not so sure why we keep seeing an increase of comments regarding VM or CCVM being faster than Boka ( LM)

I’d like to know where this idea come from ?

Reflux ratio , packing type , hieght of column ... all these things effect purity . How does still head type. alter any of that ?

Don't know about others, but I am personally referring to take-off rate, not purity etc. The needle valve in a boka or other LM is the bottleneck. Of course, I may be confounding other factors in my point of view, not comparing apples with apples. If I'm wrong, I'll edit my post above [EDIT: actually I'm not waiting, I can see what I need to change so I'm going to edit it right now]

[bluefish_dist]

IMHO the advantage of a vm, either ccvm or vm is they are easy to identify tails. They are also constant reflux vs constant takeoff like a lm.
On a lm the takeoff is constant and as alcohol in the boiler reduces the takeoff becomes a larger % of what is boiled off, meaning you need to adjust more often to hold the same abv. On the vm, the takeoff rate is reduced as alcohol is depleted making them a little more stable.

[Saltbush Bill]

IMHO the advantage of a vm, either ccvm or vm is they are easy to identify tails

Any reflux still of 2 inch or smaller is going to be slow if its re fluxing enough to be doing its job properly.
Is it really any harder to identify tails when using a Boka? a couple of points of a degree change in temp on the thermometer and a quick taste / smell of the product and your soon pretty sure of where the run is.
Reflux stills are slow by their very nature, small diameter and lack of length doesn't help things.

[Yummyrum]

a couple of points of a degree change in temp on the thermometer and a quick taste / smell of the product and your soon pretty sure of where the run is.

Hang on ......Did I just see the Salty one justifying the use of a Thermometer ...wonders will never cease

But I do agree

[Saltbush Bill]

Yes they have a use for somethings...dont think youve ever seen me say they have no use on a boka.

[cayars]

I am not so sure why we keep seeing an increase of comments regarding VM or CCVM being faster than Boka ( LM)

I’d like to know where this idea come from ?

Reflux ratio , packing type , hieght of column ... all these things effect purity . How does still head type. alter any of that ?

Could it be that people running CCVMs can use them to easily strip with in pot mode quickly and not just use them for refluxing. That can allow you to do 3 fast strips before you reflux and then have higher ABV in the still for the reflux?

[Yummyrum]

I am not so sure why we keep seeing an increase of comments regarding VM or CCVM being faster than Boka ( LM)

I’d like to know where this idea come from ?

Reflux ratio , packing type , hieght of column ... all these things effect purity . How does still head type. alter any of that ?

Could it be that people running CCVMs can use them to easily strip with in pot mode quickly and not just use them for refluxing. That can allow you to do 3 fast strips before you reflux and then have higher ABV in the still for the reflux?

Sure thing Cayers .

But this was my issue :
When folk hear Boka , VM, CM, LM...and even CCVM they think reflux still ...and really ...if you are using Coolant , Vapour or Liquid Management you would be using it in a Reflux situation .

And all these as discussed above will run at pretty much the same speed as each other producing the same product when used as a reflux still

The problem is that when not used as a reflux still IE as a stripper each will have their various quirks .
In the case of the LM and Boka , it is ...as correctly pointed out by Fivey ...( thank-you Fivey ...I did not express that to you for correcting your post ), due to the restriction imposed by the small bore of the needle valve normally fitted to such stills .
How ever it could be also argued that a VM can't do better than 1:1 in stripping mode .

So the thing is that when these stills are used contrary to how they were really designed to operate ..IE ..as reflux stills , that these limitations revile themselves and so it is unfair to quote these limitations in speed in a general comment .( CCVM is a special case )

It's these sorts of flippant comments with no validation to the mode of operation that can confuse beginners and sadly , be regurgitated by those who read and repeat without any real understanding of what they have read . This perpetuates miss-information .

[The Baker]

I admit, yummy, that I did not well understand all this either.

I was on distilling forums when Alex Bokakob first proposed his still! A real innovation at the time, way before flutes.

But, recently, there seem to have been a number of assertions that the Boka is slower than other REFLUX stills.
If I understand you that is not so.

Therefore (ignoring CCVM) if I lined up different stills of similar capacity (same sized tube, same heat input, adequate reflux [same packing material] and same reflux and product condensers) the Boka would be as fast (not what I meant really, I am not going for speed) would perform at a similar rate to the others.
And of course the product would be as good.

Just wanted to know; I have always liked the idea of a Boka, and have even seen a modular column insert for a Boka for sale.

What do you all think?

Geoff

[Yummyrum]

So hoping to add something useful to this topic this time

I went from a 2" VM to a 4" VM
Both had a packed 1 Meter column . The 4" can produce close to 4x the 2".
However as has been said , everything has to be scaled up .
Tonight I'm running just under 50 liters of strip diluted to 42% ABV ...(* would have gone 40% but I needed at least a bit of space at the top . )

So I'm pulling 95% AVB ( sample cooled down to 20 degC in the fridge) at 3.85 liters per hour .

But I am running gas so hard to keep it just under flooding for max efficiency that the flames are crazy high . I got heat deflectors around keg bottom to keep heat in . What I'm trying to say is that a standard 50 liter keg is just too small for a 4" column to keep it safely and efficiently running off gas . It really needs a wider bottomed boiler . I don't know how my gas power converts to electricity but I am pretty sure my switch board couldn't handle it ...hence gas .
I flipped down the heat shields so you can see the flame . Its stupid big . When running a flute , its just a small 1/2" flame above the burners ...to get enough power to run a 4" reflux column for neutral, needs massive amounts of heat

And all that heat has to be cooled . In winter my 2000 liter tank pisses it in . Now its summer , its really pushing it . Fine if you are on cheap water and can buy it cheap and send it down the drain but if you are recycling it , think again.
So far I've only collected about 8 liters but the water in the tank is so hot I could burn taking a bath in it . I may have to abort soon as I don't thing the reflux condenser can keep this run up .

My point being Big is better but it has its limits
There is a lot of practical sense in a 3" reflux column ...just say'n.....LOL , I might change my tune again in winter

[Yummyrum]

I admit, yummy, that I did not well understand all this either.

I was on distilling forums when Alex Bokakob first proposed his still! A real innovation at the time, way before flutes.

But, recently, there seem to have been a number of assertions that the Boka is slower than other REFLUX stills.
If I understand you that is not so.

Therefore (ignoring CCVM) if I lined up different stills of similar capacity (same sized tube, same heat input, adequate reflux [same packing material] and same reflux and product condensers) the Boka would be as fast (not what I meant really, I am not going for speed) would perform at a similar rate to the others.
And of course the product would be as good.

Just wanted to know; I have always liked the idea of a Boka, and have even seen a modular column insert for a Boka for sale.

What do you all think?

Geoff

Thank you Geoff . Pleased that cleared it up for you . If clever old fellas like you that have been around since the beginning are getting confused by this sort of miss information then I'm pleased I called it .

[Yummyrum]

So far I've only collected about 8 liters but the water in the tank is so hot I could burn taking a bath in it . I may have to abort soon as I don't thing the reflux condenser can keep this run up .
Coolant tank.jpg

My point being Big is better but it has its limits

Well Dammm ...mozzed myself there . Got about another 1.5 liters and know I have heaps to go but tails was there on the " on the fly taste tester spoon" .
Climbed the ladder and there was vapour burning my arm at the top of the Reflux condenser.
Coolant tank just couldn't keep up with the demands .

Had to shut her down
Cool change coming on Saturday...Rain they say ....hope that tank cools down .We on tank water and house tank down to 4000 liters so won't be any more distilling happening here for awhile.

[cayars]

Yummyrum, that was a pretty good explanation I think a lot of people will understand, nicely done.

Part of the problem when talking speeds of different still types is the mode they are running in. Just because it can be a reflux still (ie ccvm or cm) doesn't mean it's always ran that way for hybrid stills.

So it would be good for people to differentiate (if unclear in context) what mode they are running when some is "faster" or for someone else to ask for clarification so it doesn't become overly confusing.

BTW, you just brought up another really good thing that a lot of people are confused about on column size. A 4" flute vs 4" reflux column are drastically different beasts as far as heating/cooling are concerned.

Very good info!